Excess male hormones in a woman-its ill effects. Diag & Tr

Endocrine Disorders

Hyperandrogenism most often presents as hirsutism, which usually arises as a result of androgen excess related to abnormalities of function in the ovary or adrenal glands.

 By contrast, virilization is rare and indicates marked elevation in androgen levels.

The most common cause of hyperandrogenism and hirsutism is polycystic ovarian syndrome (PCOS).

There are only two major criteria for the diagnosis of PCOS: anovulation and the presence of hyperandrogenism as established by clinical or laboratory means. Patients with PCOS frequently exhibit insulin resistance and hyperinsulinemia.

TR:- 1) Combination oral contraceptives (OCs) decrease adrenal and ovarian androgen production and reduce hair growth in nearly two-thirds of hirsute patients.

2) Because hyperinsulinemia appears to play a role in PCOS-associated anovulation, treatment with insulin sensitizers may shift the endocrine balance toward ovulation and pregnancy, either alone or in combination with other treatment modalities.

3) Excluding cases that are of iatrogenic or factitious etiology,

4)  adrenocorticotropic hormone-independent forms of Cushing syndrome are adrenal in origin.

5) Adrenal tumors are usually very large by the time Cushing syndrome is manifest.

6) Congenital adrenal hyperplasia is transmitted as an autosomal recessive disorder. Deficiency of 21-hydroxylase is responsible for more than 90% of cases of adrenal hyperplasia resulting from an adrenal enzyme deficiency.

virilization

Patients with severe hirsutism, virilization, or recent and rapidly progressing signs of androgen excess require careful investigation for the presence of an

1)          Androgen-secreting neoplasm. Ovarian neoplasms are the most frequent androgen-producing tumors.

 Prolactin & microadenoma (> 1cm)

Elevations in prolactin may cause amenorrhea or galactorrhea. Amenorrhea with-out galactorrhea is associated with hyperprolactinemia in approximately 15% of women. In patients with both galactorrhea and amenorrhea, approximately two-thirds will have hyperprolactinemia; of those, approximately one-third will have a pituitary adenoma. In more than one-third of women with hyperprolactinemia, a radiologic abnormality consistent with a microadenoma (> 1cm) is found.

Because levels of thyroid-stimulating hormone (TSH) are sensitive to excessive or deficient levels of circulating thyroid hormone, and because most disorders of hyperthyroidism and hypothyroidsm are related to dysfunction of the thyroid gland, TSH levels are used to screen for these disorders. The most common thyroid abnormalities in women, autoimmune thyroid disorders, represent the combined effects of the multiple antibodies produced. Severe primary hypothyroidism is associated with amenorrhea or anovulation. The classic triad of exophthalmos, goiter, and hyperthyroidism in Graves disease is associated with symptoms of hyperthyroidism.

The endocrine disorders encountered most frequently in gynecologic patients are those related to disturbances in the regular occurrence of ovulation and accompanying menstruation. The most prevalent are those characterized by androgen excess, often with insulin resistance, including what is arguably the most common endocrinopathy in women— polycystic ovary syndrome (PCOS).other conditions leading to ovulatory dysfunction, hirsutism, or virilization, and common disorders of the pituitary and thyroid glands associated with reproductive abnormalities, are reviewed in this chapter.

Hyperandrogenism

Hyperandrogenism most often presents as hirsutism, which arises as a result of androgen excess related to abnormalities of function in the ovary or adrenal gland, constitutive increase in expression of androgen effects at the level of the pilosebaceous unit, or a combination of the two. By contrast, virilization is rare and indicates marked elevations in androgen levels. An ovarian or adrenal neoplasm that may be benign or malignant commonly causes virilization.

Hirsutism

Androgen effects on hair vary in relation to specific regions of the body surface. Hair that shows no androgen dependence includes lanugo, eyebrows, and eyelashes. The hair of the limbs and portions of the trunk exhibits minimal sensitivity to androgens. Pilosebaceous units of the axilla and pubic region are sensitive to low levels of androgens, such that the modest androgenic effects of adult levels of androgens of adrenal origin are sufficient for substantial expression of terminal hair in these areas. Follicles in the distribution associated with male patterns of facial and body hair (midline, facial, inframammary) require higher levels of androgens, as seen with normal testicular function or abnormal ovarian or adrenal androgen production. Scalp hair is inhibited by gonadal androgens, in varying degrees, as determined by age and genetic determination of follicular responsiveness, resulting in the common frontal-parietal balding seen in some males and in virilized females. Hirsutism results from both increased androgen production and skin sensitivity to androgens. Skin sensitivity depends on the genetically determined local activity of 5a-reductase, the enzyme that converts testosterone to dihydrotestosterone (DHT), the bioactive androgen in hair follicles.

Role of Androgens

Androgens and their precursors are produced by both the adrenal glands and the ovaries in response to their respective trophic hormones, adrenocorticotropic hormone (ACTH) and luteinizing hormone (LH), respectively . Biosynthesis begins with the rate-limiting conversion of cholesterol to pregnenolone by side-chain cleavage enzyme. There-after, pregnenolone undergoes a two-step conversion to the 17-ketosteroid DHE along the D-5 steroid pathways. This conversion is accomplished by CYP17, an enzyme with both 17a-hydroxylase and 17, 20-lyase activities. In a parallef fashion, progesterone undergoes transformation to androstenedione in the D-4 steroid pathways. The metabolism of D-5 to D- intermediates is accomplished via a D-5-isomerase, 3β-hydroxysteroid dehydrogenase (3β-HSD).

Testosterone

Approximately half of a women’s serum testosterone is derived from peripheral conversion of secreted androstenedione and the other half is derived from direct glandular (ovarian and adrenal) secretion. The ovaries and adrenal glands contribute almost equally to testosterone production in women. The contribution of the adrenals is achieved primarily through secretion of androstenedione.

Approximately 66% to 78% of circulatory testosterone is bound to sex hormone-binding globulin (SHBG) and is considered biologically inactive. Most of the proportion of serum testosterone that is not bound to SHBG is weakly associated with albumin (20% to 32%). A small percentage (1% to 2%) of testosterone is entirely unbound or free. The fraction of circulating testosterone that is unbound by SHBG has an inverse relationship with the SHBG concentration. Increased SHBG levels are noted in conditions associated with high estrogen levels. Pregnancy, the luteal phase, use of estrogen (including oral contraceptives), and conditions causing elevated thyroid hormone levels and cirrhosis of the liver are associated with reduced fractions of free testosterone caused by elevated SHBG levels. Conversely, levels of SHBG decrease and result in elevated free testosterone fractions in response to androgens, androgenic disorders (PCOS, adrenal hyperplasia or neoplasm, Cushing syndrome), androgenic medications (i.e., progestational agents with androgenic biologic activities, such as danazol, glucocorticoids, and growth hormone), hyperinsulinemia, obesity, and prolactin.

 

Major steroid biosynthesis pathway.

Laboratory Assessment of Hyperandrogenemia

In hyperandrogenic states, increases in testosterone production are not proportionately reflected in increased total testosterone levels because of the depression of SHBG levels that occurs concomitant with increasing androgen effects on the liver. Therefore, when moderate hyperandrogenism, characteristic of many functional hyperandrogenic states, occurs, elevations in total testosterone levels may remain within the normal range, and only free testosterone levels will reveal the hyperandrogenism. Severe hyperandrogenism, as occurs in virilization and that results from neoplastic production of testosterone, is reliably detected by measures of total testosterone. Therefore, in practical clinical evaluation of the hyperandrogenic patient, determination of the total testosterone level in concert with clinical assessment is frequently sufficient for diagnosis and management. When more precise delineation of the degree of hyperandrogenism is desired, measurement or estimation of free testosterone levels can be undertaken and will more reliably reflect increases in testosterone production. These measurements are not necessary in evaluating the majority of patients, but they are common in clinical research studies and may be useful in some clinical settings. Because many practitioners measure some form of testosterone level, they should understand the methods used and their accuracy. Although equilibrium dialysis is the gold standard for measuring free testosterone, it is expensive, complex, and usually limited to research settings, in a clinical setting; free testosterone levels can be estimated by assessment of testosterone binding to albumin and SHBG.

Testosterone that is nonspecifically bound to albumin (AT), is linearly related to free testosterone (FT) by the equation:

AT=K_a [A] x FT,

Where AT is the albumin-bound testosterone, K_a is the association constant of albumin for testosterone, and [A] is the albumin concentration.

In many cases of hirsutism, albumin levels are within a narrow physiologic range and thus do not significantly affect the free testosterone concentration. When physiologic albumin levels are present, the free testosterone level can be estimated by measuring the total testosterone and SHBG. In individuals with normal albumin levels, this method has reliable results compared with those of equilibrium dialysis. It provides a rapid, simple, and accurate determination of the total and calculated free testosterone level and the concentration of SHBG.

The bioavailable testosterone level is based on the relationship of albumin and free testosterone and incorporates the actual albumin level with the total testosterone and SHBG. This combination of total testosterone, SHBG, and albumin level measurements can be applied to derive a more accurate estimate of available bioactive testosterone and thus the androgen effects derived from testosterone.

Bioactive testosterone determined in this manner provides a superior estimate of the effective androgen effect derived from testosterone .

Pregnancy can alter the accuracy of measurements of bioavailable testosterone. During pregnancy, estradiol, which shares with testosterone a high affinity for SHBG, occupies a large proportion of SHBG binding sites, so that measurement of SHBG levels can overestimate the binding capacity of SHBG for testosterone. Derived estimates of free testosterone, as opposed to direct measure by equilibrium dialysis, are therefore inaccurate during pregnancy. Testosterone measurements in pregnancy are primarily of interest when autonomous secretion by tumor or luteoma is in question, and for these, total testosterone determinations provide sufficient information for diagnosis.

For testosterone to exert its biologic effects on target tissues, it must be converted into its active metabolite, DHT, by 5a-reductase (a cytosolic enzyme that reduces testosterone and androstenedione).

 Two isozymes of 5a-reductase exist; type 1, which predominates in the skin, and type 2, or acidic 5a-reductase, which is found in the liver, prostate, seminal vesicles, and genital skin. The type 2 isozyme has a 20-fold higher affinity for testosterone than type 1. Both type 1 and 2 deficiencies in males result in ambiguous genitalia, and both isozymes may play a role in androgen effects on hair growth. Dihydrotestosterone is more potent than testosterone, primarily because of its higher affinity and slower dissociation from the androgen receptor. Although DHT is the key intracellular mediator of most androgen effects, measurements of circulating levels are not clinically useful.

The relative androgenecity of androgens is as follows:

DHT=300

Testosterone=100

Androstenedione=10

DHEAS=5.

Until adrenarche, androgen levels remain low. Around 8 years of age, adrenarche is heralded by a marked increase in DHEA and DHEAS. The half-life of free DHEA is extremely short (about 30 minutes) but extends to several hours if DHEA is sulfated. Although no clear role is identified for DHEAS, it is associated with stress and levels decline steadily throughout adult life. After menopause, ovarian estrogen secretion ceases, and DHEAS levels continue to decline, whereas testosterone levels are maintained or may even increase. Although postmenopausal ovarian steroidogenesis contributes to testosterone production, testosterone levels retain diurnal variation, reflecting an ongoing and important adrenal contribution. Peripheral aromatization of androgens to estrogens increases with age, but because small fractions (2% to 10%) of androgens are metabolized in this fashion, such conversion is rarely of clinical significance.

Laboratory Evaluation Menstrual dysfunction, infertility, significant acne, obesity, or clitoromegaly.

The 2008 Endocrine Society Clinical Practice Guidelines suggest testing for elevated androgen levels in women with moderate (Ferriman-Gallwey hirsutism score 9 or greater) or severe hirsutism or hirsutism of any degree when it is sudden in onset, rapidly progressive, or associated with other abnormalities such as menstrual dysfunction, infertility, significant acne, obesity, or clitoromegaly. These guidelines suggest against testing for elevated androgen levels in women with isolated mild hirsutism because the likelihood or identifying a medical disorder that would change management or outcome is estremely low . Medications that cause hirsutism are listed and should be considered .

When laboratory testing for the assessment of hirsutism is indicated, either a bioavailable testosterone level (includes a total testosterone, SHBG, and albumin level) or a calculated free testosterone level (if albumin levels are assumed to be normal) provides the most accurate assessment of the androgen effect derived from testosterone. In clinical situations requiring a testosterone evaluation, the addition of 17-hydroxyprogesterone will screen for adult onset adrenal hyperplasia, when indicated . When hirsutism is accompanied by absent or abnormal menstrual periods, assessment of prolactin and thyroid-stimulating hormone (TSH) values are required to diagnose an ovulatory disorder.

Hypothyroidism and hyperprolactinemia may result in reduced levels of SHBG and may increase the fraction of unbound testosterone levels, occasionally resulting in hirsutism.

In cases of suspected Cushing syndrome, patients should undergo screening with a 24-hour urinary cortisol (most sensitive and specific) assessment or an overnight Dexamethasone suppression test. For this test, the patient takes 1 mg of Dexamethasone at 11 p.m, and a lobod cortisol assessment is performed at 8 a.m. the next day. Cortisol levels of 2μg/dL or higher after overnight dexamethasone suppression require a further workup for evaluation of Cushing syndrome.

Elevated 17-hydroxyprogesterone (17-OHP) levels identify patients who may have AOAH, found in 1% to 5% of hirsute women. The 17-OHP levels can vary significantly within the menstrual cycle, increasing in the periovulatory period and luteal phase, and may be modestly elevated in PCOS. Standardized testing requires early morning testing during the follicular phase.

According to the Endocrine Society clinical guideline, patients with morning follicular phase 17-OHP levels of less than 300 ng/dL (10 nmol/L) are likely unaffected .When levels are greater than 300 ng/dL but less than 10,000 ng/dL (300 nmol/L), ACTH testing should be performed to distinguish between PCOS and AOAH. Levels greater than 10,000 ng/dL (300 nmol/L) are virtually diagnostic of congenital adrenal hyperplasia.

Precocious pubarche precedes the diagnosis of adult onset congenital adrenal hyperplasia in 5% to 20% of cases. Measurement of 17-OHP should be performed in patients presenting with precocious Pubercahe, and a subsequent ACTH stimulation test is recommended if basal 17-OHP is greater than 200 ng/dL. A study using a 200 ng/dL threshold for basal 17-OHP plasma levels to prompt ACTH stimulation testing offered 100% (95 % confidence interval sensitivity and 99% specificity for the diagnosis of adult onset congenital adrenal hyperplasia within the cohort with precocious puberty .

Because increased testosterone production is not reliably reflected by total testosterone levels, the clinician may chose to rely on typical male pattern hirsutism as confirmation of its presence, or may elect measures that reflect levels of free or unbound testosterone (bioavailable or calculated free testosterone levels).

Total testosterone does serve as a reliable marker for testosterone-producing neoplasms. Total testosterone levels greater than 200 ng/dL should prompt a workup for ovarian or adrenal tumors.

Although the ovary is the principal source of androgen excess in most of PCOS patients, 20% to 30% of patients with PCOS will demonstrate supranormal levels of DHEAS. Measuring circulating levels of DHEAS has limited diagnostic value, and overinterpretation of DHEAS levels should be avoided .

In the past, testing for androgen conjugates (e.g.,3a-androstenediol G [3a-diol G] and androsterone G [AOG] as markers for 5a-reductase activity in the skin) was advocated. Routine

 

Evaluation of hirsute women for hyperandrogenism.

Evaluation includes more than the assessment of the degree of hirsutism. When hirsutism is moderate (>9) or severe or if mild hirsutism is accompanied by features that suggest an underlying disorder, elevated androgen levels should be ruled out. Disorders to be considered include endocrinopathies, of which PCOS is the most common, and neoplasms. Plasma testosterone is best assessed in the early morning on day 4 to 10 in regularly cycling women. A 17-hydroxyprogesterone is also indicated when symptoms warrant a bioavailable testosterone measurement.

3β-hydroxysteroid dehydrogenase deficiency in severe forms presents with mineralocorticoid and cortisol deficiency. Mild forms are diagnosed with a mean post-ACTH (1-24) stimulation: 17-hydroxypregnenolone/17-hydroxyprogesterone ration of 11 compared to 3.4 in normals. 11β-hydroxylase deficiency presents with hypertension in the first years of life in two thirds of patients. The mild form presents with vitalization or precocious puberty without hypertension. Undiagnosed adults demonstrate hirsutism, acne, and amenorrhea. Diagnosis in confirmed with an 11-desoxycortisol level >25 ng/mL 60 minutes after ACTH (1-24) stimulation. ACTH( adrenocorticotropic hormone); AOAH( adult-onset adrenal hyperplasia) DHEAS( dehydroepiandrosterone sulfate; HAIR-AN, hyperandrogenemia, insulin resistance acanthosis nigricans. (

Medications Associated with Hirsutism

Acetazolamide                                                                               methyldopa

anabolic steroids                                                                           minoxidil

androgenic progestins                                         penicillamine

androgens                                                            phenothiazines

Cyclosporine                                                           phenytoin

Diazoxide                                                                streptomycin

DHEA                                                                        reserpine

heavy metals                                                          valproic acid

Interferon

Determination of androgen conjugates to assess hirsute patients is not recommended, because hirsutism itself is an excellent bioassay of free testosterone action on the hair follicle and because these androgen conjugates arise from adrenal precursors and is likely markers of adrenal and not ovarian steroid production (8).

In the zona reticularis layer of the adrenal cortex, DHEAS is generated y SULT2A1 (9). This layer of the adrenal cortex is thought to be the primary source of serum DHEAS, DHEAS levels decline as a personages and the reticularis layer diminishes in size. In most laboratories, the upper limit of a DHEAS level is 350 μg/dL (9.5 nmol/L). A random sample is sufficient because the level of variation is minimized as a result of the long half-life characteristic of sulfated steroids. DHEAS is used as a screen for androgen-secreting adrenocortical tumors; however, moderate elevations are a common finding in the presence of PCOS, obesity, and stress, whichreduces specificity (10).

A study of women with androgen-secreting adrenocortical tumors (ACT-AS) (N-44), compared to women with nontumor androgen excess (NTAE) (N=102), sheds additional light on the choice of hormones used to screen for an adrenocortical tumor. In the study, the demographics and the prevalence of hirsutism, acne, oligomenorrhea and amenorrhea were not different in each group. Free testosterone (free T) was the most commonly elevated androgen in ACT-AS (94%), followed by androstenedione (A) (90%), DHEAS (82%), and total testosterone (total T) (76%),

Table 31.2 Normal Values for Serum Androgensa
Testosterone (total)	20-80 ng/dL
Free testosterone (calculated)	0.6-6.8 pg/mL
Percentage free testosterone	0.4-2.4%
Bioavailable testosterone	1.6-19.1 ng/dL
SHBG	18-114 nmol/L
Albumin	3,300-4,800 mg/dL
Androstenedione	20-250 ng/dL
Dehydroepiandrosterone sulfate	100-350 μg/dL
17-hydroxyprogesterone (follicular phase)	30-200 ng/dL

SHBG, sex hormone-binding globulin.

^aNormal values may vary among different laboratories. Free testosterone is calculated using measurements for total testosterone and sex hormone-binding globulin, whereas bioavailable testosterone is calculated using measured total testosterone, sex hormone-binding globulin, and albumin. Calculated values for free and bioavailable testosterone compare well with equilibrium dialysis methods of measuring unbound testosterone when albumin levels are normal. Bioavailable testosterone includes free plus very weakly bound (non-SHBG, nonalbumin) testosterone. Bioavailable testosterone is the most accurate assessment of bioactive testosterone in the serum without performing equilibrium dialysis.

When clinical signs of androgen excess reach the point of virilization or the free testosterone level is above 6.85 pg.mL, (23.6 pmol/L), follow-up testing with a 11-desoxycortisol (>7 ng/mL), DHEAS (>3.6 μg per day) are the most sensitive and specific for the detection of an androgen-secreting adrenocortical tumor. Careful consideration of the sensitivity and specificity, diurnal variation, and age-related variation of potentially measureable androgens will aid in choosing the most useful measurements (Table 31.3).

Polycystic Ovary Syndrome

PCOS is arguably one of the most common endocrine disorders in women of reproductive age, affecting 5% to 10% of women worldwide. This familial disorder appears to be inherited as a complex genetic trait (13). It is characterized by a combination of hyperandrogenism (either clinical or biochemical), chronic anovulation, and polycystic ovaries. It is frequently associated with insulin resistance and obesity (14). PCOS receives considerable attention because of its using the Rotterdam PCOS Diagnostic Criteria, the presence of two of the three criteria is sufficient to diagnosis PCOS; menstrual cycle anomalies (amenorrhoea, oligomenorrhea), clinical and/or biochemical hyperandrogenism, and/or the ultrasound appearance of polycystic ovaries after all other diagnoses are ruled out. Other pathologies that can result in a PCOS phenotype include AOAH, adrenal or ovarian neoplasm, Cushing syndrome, hypo or hypergonadotropic disorders, hyperprolactinemia, and thyroid disease (Fig. 31.4)

All other frequently encountered manifestations offer less consistent findings and therefore qualify only as minor diagnostic criteria for PCOS. They include elevated LH-to-FSH (follicle-stimulating hormone) ratio, insulin resistance, perimenarchal onset of hirsutism, and obesity.

Clinical hyperandrogenism includes hirsutism, male pattern alopecia, and acne (19). Hirsutism occurs in approximately 70% of patients with PCOS in the United States and in only 10% to 20% of patients with PCOS in Japan (20, 21). A likely explanation for this discrepancy is the genetically determined differences in skin 5a-reducates activity (22, 23).

Nonclassic adrenal hyperplasia and PCOS may present with similar clinical features. It is important to measure the basal follicular phase 17-hydroxyprogesterone level in all women presenting

Table 31.4 Revised Diagnostic Criteria of Polycystic Ovary Syndrome

1990 Criteria (both 1 and 2)

Chronic anovulation and

Clinical and/or biochemical signs of hyperandrogenism and exclusion of other etiologies.

Revised 2003 criteria (2 out of 3)

Oligoovualtion or anovulation

Clinical and/or biochemical signs of hyperandrogenism

Polycystic ovaries and exclusion of other etiologies (congenital adrenal hyperplasia, androgen-secreting tumors, Cushing’s syndrome)

From Rotterdam ESHRE/ASRM-Sponsored PCOS Consensus Workshop Group. Revised 2003 consensus on diagnostic criteria and long-term health risks related to polycystic ovary syndrome. Fertile Steril 2004; 81:19-25, with permission.

 

Figure 31.4 diagnostic algorithm for polycystic ovary syndrome, (From Rosenfield RL. Clinical practice. Hirsutism. N Engl J Med 2005; 353: 2578-2588, with permission.)

With hirsutism to exclude the presence of nonclassic congenital adrenal hyperplasia, regardless of the presence of polycystic ovaries or metabolic dysfunction (24).

The menstrual dysfunction in PCOS arises from anovulation or oligo-ovulation and ranges from amenorrhea to oligomenorrhea. Regular menses in the presence of anovulation in PCOS is uncommon, although one report found that among hyperandrogenic women with regular menstrual cycles, the rate of anouvlation is 21% (25). Classically, the disorder is lifelong, characterized by abnormal menses from puberty with acne and hirsutism arising in the teens. It may arise in adulthood, concomitant with the emergence of obesity, presumably because this is accompanied by increasing hyperinsulinemia (26).

The sonographic criteria for PCO requires the presence of 12 or more follicles in either ovary measuring 2 to 9 mm in diameter and/or increased ovarian volume (>10mL). a single ovary meeting these criteria is sufficient to affix the PCO diagnosis (19). The appearance of PCO on ultrasound scanning is common. Only a fraction of those with PCO appearance have the clinical and/or endocrine features of PCOS. A PCO appearance is found in about 23% of women of reproductive age, while estimates of the incidence of PCOS vary between 5% and 10% (27). Polycystic appearing ovaries in women with PCOS was not associated with increased cardiovascular disease risk, independent of body mass index (BMI), age insulin levels (28). An English study demonstrated that without symptoms of polycystic ovary syndrome, a PCO appearance alone is not associated with impaired fecundity or fertility (29).

Obesity occurs in more than 50% of patients with PCOS. The body fat is usually deposited centrally (android obesity), and a higher waist-to-hip ratio is associated with insulin resistance indicating an increased risk of diabetes mellitus and cardiovascular disease (30). Among women with PCOS, there is widespread variability in the degree of adiposity by geographic location and ethnicity. In studies in Spain, China, Italy, and the United State, the percentage of obese women with PCOS were 20%, 43%, 38%, and 69%, respectively (31).

Insulin resistance resulting in hyperinsulinemia is commonly exhibited in PCOS.  Insulin resistance may eventually lead to the development of hyperglycemia and type 2 diabetes mellitus (32). About one-third or obese PCOS patients have impaired glucose tolerance (IGT), and 7.5% to 10% have type 2 diabetes mellitus (33). These rates are mildly increased in nonobese women who have PCOS (10% IGT; 1.5% diabetes, respectively), compared with the general population of the United States (7.8% IGT; 1% diabetes, respectively) (34, 35).

Abnormal lipoproteins are common in PCOS and include elevated total cholesterol, triglycerides, and low-density lipoproteins (LDL); and, low levels of high-density lipoproteins (HDL), and apoprotein A-I (30, 36). According to one report, the most characteristic lipid alteration is decreased levels of HDL_2a (37).

Other observation in women with PCOS include impaired fibrinolysis, as shown by elevated circulating levels of plasminogen activator inhibitor, an increased  incidence of hypertension over the years (which reaches 40% by perimenopause), a greater prevalence of atherosclerosis and cardiovascular disease, and an estimated sevenfold increased risk for myocardial infarction (36,38-41).

Pathology

Macroscopically, ovaries in women with PCOS are two to five times the normal size. A cross-section of the surface of the ovary discloses a white, thickened cortex with multiple cysts that are typically less than a centimeter in diameter. Microscopically, the superficial cortex is fibrotic and hypocellular and may contain prominent blood vessels. In addition to smaller atretic follicles, there is an increase in the number of follicles with luteinized theca interna. The stroma may contain luteinized stromal cells (42).

Pathophysiology and Laboratory Findings

The hyperandrogenism and anovulation that accompany PCOS may be caused by abnormalities in four endocrinologically active compartments; (i) the ovaries, (ii) the adrenal glands, (iii) the periphery (fat), and (iv) the hypothalamus-pituitary compartment (Fig.31.5).

In patients with PCOS, the ovarian compartment is the most consistent contributor of androgens. Dysregulation of CYP17, the androgen-forming enzyme in both the adrenals and the ovaries, may be one of the central pathogenetic mechanisms underlying hyperandrogenism in PCOS (43). The ovarian stroma, theca, and granulose contribute to ovarian hyperandrogenism and are stimulated by LH (44). This hormone relates to ovarian androgenic activity in PCOS in a number of ways.

Total and free testosterone levels correlate directly with LH levels (45).

The ovaries are more sensitive to gonadotropic stimulation, possibly as a result of CYP17 dysregulation (43).

Treatment with a gonadotropin-releasing hormone (GnRH) agonist effectively suppresses serum testosterone and androstenedione levels (46).

Larger doses of a GnRH agonist are required for androgen suppression than for endogenous gonadotropin-induced estrogen suppression (47).

The increased testosterone levels in patients with PCOS are considered ovarian in origin. The serum total testosterone levels are usually no more than twice the upper normal range (20 to 80 ng/dL). However, in ovarian hyperthecosis, values may reach 200 ng/dL or more (48). The adrenal compartment plays a role in the development of PCOS. Although the hyperfunctioning CYP17 androgen-forming enzyme coexists in both the ovaries and the adrenal glands, DHEAS is increased in only about 50% of patients with PCOS (49, 50). The hyperre-sponsiveness of DHEAS to stimulation with ACTH, the onset of symptoms around puberty, and the observation of 17, 20-lyase activation (one of the two CYP17 enzymes) are key events in adrenarche that led to the hypothesis that PCOS arises as an exaggeration of adrenarche (48).

The peripheral compartment, defined as the skin and the adipose tissue, manifests its contribution to the development of PCOS in several ways.

The presence and activity of 5a-reductase in the skin largely determines the presence or absence of hirsutism (22, 23).

Aromatase and 17β-hydroxysteroid dehydrogenase activities are increased in fat cells and peripheral aromatization is increased with increased body weight (51, 52).

With obesity the metabolism of estrogens, by way of reduced 2-hydroxylation and 17a-oxidation, is decreased and metabolism via estrogen active 16-hydroxyestrogens (estriol) is increased (53).

Whereas estradiol (E2) is at a follicular phase level in patients with PCOS, estrone (E1) levels are increased as a result of peripheral aromatization of androstendione (54).

A chronic hyperestrogenic state, with reversal of the E1-to-E2 ratio, results and is unopposed by progesterone.

The hypothalamic-pituitary compartment participates in aspects critical to the development of PCOS.

An increase in LH pulse frequency relative to those in the normal follicular phase is the result of increased GnRH pulse frequency (55).

This increase in LH pulse frequency explains the frequent observation of an elevated LH and LH-to-FSH ratio.

FSH is not increased with LH, likely because of the combination of increased gonadotropin pulse frequency and the synergistic negative feedback of chronically elevated estrogen levels and normal follicular inhibin.

About 25% of patients with PCOS exhibit mildly elevated prolactin levels, which may result from abnormal estrogen feedback to the pituitary gland. In some patients with PCOS, bromocriptine has reduced LH levels and restored ovulatory function (56).

Polycystic ovary syndrome is a complex multigenetic disorder that results from the interaction between multiple genetic and environmental factors. Genetic studies of PCOS reported allele sharing in large PCOS patient populations and linkage studies focused on candidate genes most likely to be involved in the pathogenesis of PCOS. These genes can be grouped in four categories: (i) insulin resistance-related genes, (ii) genes that interfere with the biosynthesis and the action of androgens, (iii) genes that encode inflammatory cytokines, and (iv) other candidate genes (57).

Linkage studies indentified the follistatin, CYP11A, Calpain 10, IRS-2 regions and locinear the insulin receptor (19p 13.3), SHBG, TCF7L2, and the insulin genes, as likely PCOS candidate genes (58-64). A polymorphic variant, D19S884, in FBN3 was found to be associated with risk of PCOS (65). Using theca cells derived from women with PCOS elevated mRNA levels was noted for CYP11A, 3BHSD2, and CYP17 genes with corresponding overproduction of testosterone, 17-a-hydroxyprogesterone, and progesterone. Despite the characteristically heightened steroidogenesis in PCOS, the STARB gene was not overexpressed (58). Microarray data using theca cells from PCOS women did not identify any genes near the 19p13.3 locus that were differentially expressed; however, the mRNAs of several genes that map to 19p13.3, including the insulin receptor, p114-Rho-GEF, and several expressed sequence tags, were detected in both PCOS and normal theca cells. Those studies identified new factors that might impact theca cell steroidogenesis and function, including cAMP-GEFII, genes involved in all-transretinoic acid (atRA) synthesis signaling, genes that participate in the Wnt signal transduction pathway, and transcription factor GATA6. These findings suggest that a 19p13.3 locus or some other candidate gene may be a signal transduction gene that results in overexpression of a suite of genes downstream that may affect steroidogenic activity (66). Polymorphisms in major folliculogenesis genes, GDF9, BMP15, AMH, and AMHR2, are not associated with PCOS susceptibility (67).

Insulin Resistance

Patients with PCOS frequently exhibit insulin resistance and hyperinsulinemia. Insulin resistance and hyperinsulinemia participate in the ovarian steroidogenic dysfunction of PCOS. Insulin alters ovarian steroidogenesis independent of godadotropin secretion in PCOS. Insulin and insulin-like growth factor I (IGF-I) receptors are present I the ovarian stromal cells. A specific defect in the early steps of insulin receptor-mediated signaling (diminished autophosphorylation) was identified in 50% of women with PCOS (68).

Insulin has direct and indirect roles in the pathogenesis of hyperandrogenism in PCOS. Insulin in collaboration with LH enhances the androgen production of theca cells. Insulin inhibits the hepatic synthesis of sex hormone-binding globulin, the main circulating protein that binds to testosterone, thus increasing the proportion of unbound or bioavailable testosterone (13).

The most common cause of insulin resistance and compensatory hyperinsulinemia is obesity, but despite its frequent occurrence in PCOS, obesity alone does not explain this important association (56).the insulin resistance associated with PCOS is not solely the result of hyperandrogenism based on the following:

Hyperinsulinemia is not a characteristic of hyperandorgenism in general but is uniquely associated with PCOS (69).

In obese women with PCOS, 30% to 45% have glucose intolerance or frank diabetes mellitus, whereas ovulatory hyperandrogenic women have normal insulin levels and glucose tolerance (69). It seems that the associations between PCOS and obesity on the action of insulin are synergistic.

Suppression of ovarian steroidogenesis in women with PCOS with long-acting GnRH analogues does not change insulin levels or insulin resistance (70).

Oophoectomy in patients with hyperthecosis accompanied by hyperinsulinemia and hyperanodrogenemia does not change insulin resistance, despite a decrease in androgen levels (70, 71).

Acanthosis nigricans is a reliable marker of insulin resistance in hirsute women. This thickened, pigmented, velvety skin lesion is most often found in the vulva and may be present on the axilla, over nape of the neck, below the breast, and on the inner thigh (72). The HAIR-AN syndrome consists of hyperandrogenism (HA), insulin resistance (IR), and acanthosis nigricans (AN) (68,73). These patients often have high testosterone levels (>150 ng/dL), fasting insulin levels of greater than 25 μIU/mL (normal <20 to 24 μIU/mL), and maximal serum insulin responses to glucose load (75 gm) exceeding 300 μIU/mL (normal is <160 μIU/m: at 2 hours postglucose load).

Screening Strategies for Diabetes and Insulin Resistance

The 2003 Rotterdam  Consensus Group recommends that obese women with PCOS and nonobese PCOS patients with risk factor for insulin resistance, such as a family history of diabetes, should be screened for metabolic syndrome, including glucose intolerance with an oral glucose tolerance test (19). The standard 2-hour oral glucose tolerance test (OGTT) provides an assessment of both degrees of hyperinsulinemia and glucose tolerance and yields the highest amount of information for a reasonable cost and risk (7).

Multiple other testing or screening schema were proposed to assess the presence of hyperinsulinemia and insulin resistance. In one the fasting glucose-to-insulin ratio is determined, and values less than 4.5 indicate insulin resistance. Using the 2-hour GTT with insulin levels, 10% of nonobese and 40% to 50% of obese PCOS women have impaired glucose tolerance (IGT=2-hour glucose level ≥ 140 but ≤190 mg/dL) or overt type 2 diabetes mellitus (any glucose level >200 mg/dL). Some research studies utilized a peak insulin level of over 150 μIU/mL or a mean level of over 84 μIU/mL over the three blood draws of a 2-hour GTT as a criteria to diagnose hyperinsulinemia.

The documentation of hyperinsulinemia using either the glucose to insulin ratio or the 2-hour GTT with insulin is problematic. When compared to the gold standard measure for insulin resistance, the hyperinsulemic-euglycemic clamp, it shows that the glucose-to-insulin ratio does not always accurately portray insulin resistance. When hyperglycemia is present, a relative insulin secretion deficit is present. This deficient insulin secretion exacerbates the effects of insulin resistance and renders inaccurate the use of hyperinsulinemia as an index of insulin resistance. Thus, routine measurements of insulin levels may not be particularly useful.

Although detection of insulin resistance, per se, is not of practical importance to the diagnosis or management of PCOS, testing women with PCOS for glucose intolwrance is of value because their risk of cardiovascular disease correlates with this finding. An appropriate frequency for such screening depends on age, BMI and waist circumference, all of which increase risk.

Interventions

Two-Hour Glucose Tolerance Test Normal Glucose Ranges (World Health Organization criteria, after 75-gm glucose load)

Fasting           64 to 128 mg/dL

One hour        120 to 170 mg/dL

Two hour       70 to 140 mg/dL

Two-Hour Glucose Values foe Impaired Glucose Tolerance and Type 2 Diabetes (World Health Organization criteria, after 75-gm glucose load)

Normal (2-hour)                               <140 mg/dL

Impaired (2-hour)                             =140 to 199 mg/dL

Type 2 diabetes mellitus (2-hour) ≥200 mg/dL

Abnormal glucose metabolism may be significantly improved with weight reduction, which may reduce hyperandrogenism and restore ovulatory function (74). In obese, insulin resistant women, caloric restriction that results in weight reduction will reduce the severity o insulin resistance (a 40% decrease in insulin level with a 10-kg weight loss) (75). This decrease in insulin levels should result in a marked decrease in androgen production (a 35% decrease in testosterone levels with a 10-kg weight loss) (76). Exercise reduces insulin resistance, independent from any associated weight loss, but data on the impact of exercise on the principal manifestations of PCOS are lacking.

In addition to addressing the increased risk for diabetes, the clinician should recognize insulin resistance or hyperinsulinemia as a cluster syndrome called metabolic syndrome or dysmetabolic syndrome X. recognition or the importance of insulin resistance or hyperinsulinemia as a risk factor for cardiovascular disease led to diagnostic criteria for the dysmetabolic syndrome. The more dysmetabolic syndrome X criteria are present, the higher the level of insulin resistance and its downstream consequences. The presence of three of the following five criteria confirm the diagnosis, and an insulin-lowering agent and/or other interventions may be warranted (19).

Metabolic Syndrome Diagnostic Criteria

Female waist                           >35 inches

Triglycerides                            >150 mg/dL

HDL                                           <50 mg/dL

Blood pressure                              >130/85 mmHg

Fasting glucose                             110-126 mg/dL

Two-hour glucose (75 gm OGTT):    140-199 mg/dL

Risk factors for the dysmetabolic syndrome include nonwhite race, sedentary lifestyle, BMI greater than 25, age over 40 years, cardiovascular disease, hypertension, PCOS, hyperandrogenemia, insulin resistance, HAIR-AN syndrome, nonalcoholic steatohepatitis (NASH), and a family history of type 2 diabetes mellitus, gestational diabetes, or impaired glucose tolerance.

Long-Term Risks and Interventions

Dyslipidemia is one of the most common metabolic disorders seen in PCOS patients (up to 70% prevalence in a US PCOS population) (78). It is associated with insulin resistance and hyperandrogenism in combination with environmental (diet, physical exercise) and genetic factors. Various abnormal patterns include decreased levels of HDL, elevated levels of triglycerides, decreased total and LDL levels, and altered LDL quality (79, 80).

To assess cardiovascular risk and prevent disease in patients with PCOS, the Androgen Excess and Polycystic Ovary Syndrome (AE-PCOS) Society recommend the following monitoring activities (80):

Waist circumference and BMI measurement at every visit, using the National Health and Nutrition Examination Survey method.

A complete lipid profile based using the American Heart Association guidelines (Fig. or sooner if weight gain occurs.

A 2-hour post-75-goral glucose challenge measurement in PCOS women with a BMI greater than 30 kg/m²_, or alternatively in lean PCOS women with advanced age (40 years), personal history of gestational diabetes, or family history or type 2 diabetes.

Blood pressure measurement at each visit. The ideal blood pressure is 120/80 or lower. Prehypertension should be treated because blood pressure control has the largest benefit in reducing cardiovascular diseases.

Regular assessment for depression, anxiety, and quality of life.

Treatment of Hyperandrogenism and PCOS

Treatment depends on a patient’s goals. Some patients require hormonal contraception, whereas other desire ovulation induction. In all cases where there is significant ovulatory dysfunction, progestational interruption of the unopposed estrogen effects on the endometrium is necessary. This may be accomplished by periodic luteal function resulting from ovulation induction, progestational supperession via contraceptive formulations, or intermittent administration of progestational agents for endometrial or menstrual regulation. Interruption of the steady state of hyperandrogenism and control of hirsutism usually can be accomplished simultaneously. Patients desiring pregnancy are an exception, and for them effective control of hirsutism may not be possible. Treatment regimens for hirsutism are listed in Table 31.6. The induction of ovulation and treatment of infertility are discussed in Chapter 32.

Table 31.6 Medical Treatment of Hirsutism
Treatment Category	Specific Regimens
Weight loss
Hormonal suppression	Oral contraceptives
	Gonadotropin-releasing hormone analogues
	Glucocorticoids
Steroidogenic enzyme inhinitors	Ketoconazole
5a-reductase inhibitiors	Finasteride
Antiandrogens	Spironolactone
	Cyproterone acetate
	Flutamide
Insulin sensitizer	Metformin
Mechanical	Temporary
	Permanent
	Electrolysis
	Laser hair removal

Insulin Sensitizers

Becauses hyperinsulinemia appears to play a role in PCOS-associated anovulation, treatment with insulin sensitizers may shift the endoctine balance toward ovulation and pregnancy, either alone or in comination with other treatment modalities.

Metfromin (Glucophage) is an oral biguanide antihyperglycemic drug used extensively for noninsulin-dependent diabetes. Metfromin is pregnancy category B drug with no known human teratogenic effect. It lowers blood glucose mainly by inhibiting hepatic glucose production and by enhancing peripheral glucose uptake. Metformin enhances insulin sensitivity at the postreceptor level and stimulates insulin-mediated glucode disposal (144).

Metfromin has been used extensively to treat oligo-ovulatory infertility, insulin resistance, and hyperandrogenism in PCOS patients. Metformin is used to treat PCOS oligo-ovulatory infertility either alone or in combination with dietary restriction, clomiphene, or gonadotropins. In randomized control studies, metformin improves the odds of ovulation in women with PCOS when compared with placebo (145, 146). A large multicenter, randomized control trial in women with PCOS concluded that clomiphene is superior to metformin in achieving live births in infertile women with PCOS. When ovulation was used as the outcome, the combination of metformin and clomiphene was superior to either clomiphene alone or metformin alone (147). Multiple births are a complication of clomiphene therapy.

The most common side effects are gastrointestinal, including nausea, vomiting, diarrhea, bloating, and flatulence. Because the drug caused fatal lactic acidosis in men with diabetes who have renal insufficiency, baseline renal function testing is suggested (148). The drug should not be given to women with elevated serum creatinine levels 144).

Concepts regarding the role of obesity and insulin resistance or hyperinsulinemia in PCOS suggest that the primary intervention should be recommending and assisting with weight loss (5% to 10% of body weight). In those with an elevated BMI, orlistat proved helpful in initiating and maintaining weight loss. A percentage of PCOS patients will respond to weight loss alone with spontaneous ovulation. In those who do not respond to weight loss alone or who are unable to lose weight, the sequential addition of clomiphene cirate followedby an insulin sensitizer, followed by the combination of these agents may promote ovulation without resorting to injectable gonadotropins.

A prevailing concern over the increased incidence of spontaneous abortions in women with PCOS and the potential reduction afforded by insulin sensitizers suggests that insulin sensitizers may be beneficial in combination with gonadotropin therapy for ovulation induction or in vitro fertilization (149). Women with early pregnancy loss have a low level of insulin-like growth factor (IGF) binding protein-1 (IGFBP-1), and of circulating glycodelin, which has immunomodulatory effects protecting the developing fetus. Use of metformin increased levels of both factors, which might explain early findings suggesting that metfrormin use may reduce the high spontaneous abortion rates seen among women with PCOS (150).

A number of observational studies suggested that metformin reduces the risk of pregnancy loss (151, 152). However, there are no adequately designed and sufficiently powered randomized controls trials to address this issue. In prospective randomized pregnancy and PCOS (PPCOS) trial, there was a concerning nonsignificant trend toward a greater rate of miscarriages on the metformin only group (151). This trend was not noted in other trials.

There are no conclusive data to support a beneficial effect of metfromin on pregnancy loss, and the trend toward a higher miscarriage rate in the PPCOS trial, which used extended release metformin, is of some concern (145, 147).

The incidence of ovarian hyperstiulation syndrome is reduced with adjuvant metformin in PCOS patients at risk for severe ovarian hyperstimulation syndrome (153).

Cushing Syndrome

The adrenal cortex produces three classes of steroid hormones: glucocorticoids, mineralocorticoids, and sex steroids (androgen and estrogen precursors). Hyperfunction of the adrenal gland can produce clinical signs of increased activity of any or all of these hormones. Increased glucocorticoid action results in nitrogen wasting and a catabolic state. This causes muscle weakness, osteoporosis, atrophy of the skin with striae, nonhealing ulcerations and ecchymoses, reduced immune resistance that increased the risk of bacterial and fungal infections, and glucose intolerance resulting from enhanced gluconeogenesis and antagonism to insulin action.

Although most patients with Cushing syndrome gain weight, some lose it. Obesity is typically central, with characteristic redistribution of fat over the clavicles around the neck and on the trunk, abdomen, and cheeks. Cortisol excess may lead to insomnia, mood disturbances, depression, and even overt psychosis. With overproduction of sex steroid precursors, women may exhibit hyperandrogenism (hirsutism, acne, oligomenorrhea or amenorrhea, thinning of scalp hair). Masculinization is rare, and its presence suggests an autonomous adrenal origin, most often an adrenal malignancy. With overproduction of mineralocorticoids, patients may manifest arterial hypertension and hypokalemic alkalosis. The associated fluid retention may cause pedal edema (Table 31.7) (154).

Characteristic clinical laboratory findings associated with hypercortisolism are confined mainly to a complete blood count showing evidence of granulocytosis and reduced levels of lymphocytes and eosinophils. Increased urinary calcium secretion may be present.

Causes

The six recognized noniatrogenic caused of Cushing syndrome can be divided between those that are ACTH dependent and those that are ACTH independent (Table 31.8). the ACTH-dependent causes can result from ACTH secreted by pituitary adenomas or from an ectopic source. The hallmark of ACTH-dependent forms of Cushing syndrome is the presence of normal or high plasma ACTH concentrations with increased cortisol levels. The adrenal glands are hyperplastic bilaterally. Pituitary ACTH-secreting adenoma, or Cushing disease, is the most common cause of endogenous Cushing syndrome (154). These pituitary adenomas are usually microadenomas (<10 mm in diameter) that may be as small as 1 mm. they behave as though they are resistant, to a variable degree, to the feedback effect of cortisol. Like the normal gland, these tumors secrete ACTH in a pulsatile fashion; unlike the.

Congential Adrenal Hyperplasia

CAH is transmitted as an autosomal recessive disorder. Several adrenocortical enzymes necessary for cortisol biosynathesis may be affected. Failure to synthesize the fully functional enzyme has the following effects:

A relative decrease in cortisol production.

A compensatory increase in ACTH levels.

Hyperplasia of the zona reticularis of the adrenal cortex.

An accumulation of the precursors of the effected enzyme in the bloodstream.

21-Hydroxylase Deficiency

Deficiency of 21-hydroxylase is responsible for over 90% of all cases of adrenal hyperplasia due to adrenal synthetic enzyme deficiency. The disorder produces a spectrum of conditions; CAH, with or without salt wasting, and milder forms that are expressed as hyperandrogenism of pubertal onset (adult onset adrenal hyperplasia, AOAH). Salt-wasting CAH, the most severe form, affects 75% of patients with congenital manifestations during the first 2 weeks of life and results in a life-threatening hypovolemic salt-wasting crisis, accompanied by hyponatremia, hyperkalemia, and acidosis. The salt-wasting form results from a severity of enzyme deficiency sufficient to result in ineffective aldosterone synthesis. With or without salt-wasting and newborn adrenal crisis, the condition is usually diagnosed earlier in affected female newborns than in males as genital virilization (e.g., clitoromegaly, labioscrotal fusion, and abnormal urethral course) is apparent at birth.

In simple virilizing CAH, affected patients are diagnosed as virilized newborm females or as rapidly growing masculinized boys at 3 to 7 years of age. Diagnosis is based on basal levels of the substrate for 21-hydroxylase, 17-OHP; in cases of congenital adrenal hyperplasia caused by 21-hydroxylase deficiency and in milder forms of the disorder with manifestations later in life (acquired, late onset, or adult-onset adrenal hyperplasia), diagnosis depends on basal and ACTH-stimulated levels of 17-OHP.

Patients with morning follicular phase 17-OHP levels of less than 300 ng/dL (10 nmol/L) are likely unaffected. When levels are greater than 300 ng/dL, but less than 10,000 ng/dL (300 nmol/L), ACTH testing should be performed to distinguish between 21-hydroxylase deficiency and other enzyme defects or to make the diagnosis in borderline cases. Levels greater than 10,000 ng/dL (300 nmol/L) are virtually diagnostic of congenital adrenal hyperplasia.

Nonclassic Adult Onset Congenital Adrenal Hyperplasia

The nonclassic type of 21-hydroxylase deficiency represents partial deficiency in 21-hydroxylation, which produces a late-onset, milder hyperandrogenemia. Its occurrence depends on some degree of functional deficit resulting from mutations affecting both alleles for the 21-hydroxylase enzyme. Heterozygote carriers for mutations in the 21-hydroxylase enzyme will demonstrate normal basal and modestly elevated stimulated levels of 17-OHP, but no abnormalities in circulating androgens. Some women with mild gene defects in both alleles demonstrate modest elevations in circulating 17-OHP concentrations, but no clinical symptoms or signs.

The hyperandrogenic symptoms of AOAH are mild and typically present at or after puberty. The three phenotypic varieties are (174):

Those with ovulatory abnormalities and features consistent with PCOS (39%)

Those with hirsutism alone without oligomenorrhea (39%)

Those with elevated circulating androgens but without symptoms (cryptic) (22%).

Precocious puberty reveals late-onset congenital adrenal hyperplasia in 5% to 20% of cases that mainly are caused by nonclassic 21-hydroxylase deficiency.

Measurement of 17-OHP should be performed in patients presenting with precocious puberty, and a subsequent ACTH stimulation test is recommended if basal 17-OHP is greater than 200 ng/dL.

The need for screening patients with hirsutism for adult-onset adrenal hyperplasia depends on the patient population. The frequency of some form of the disorder varies by ethnicity and is estimated at 0.1% of the general population, 1% to 2% of Hispanics and Yugoslavs, and 3% to 4% of Ashkenazi Jews (175).

Genetics of 21-hydroxylase Deficiency

The 21-hydroxylase gene is located on the short arm of chromosome 6, in the midst of the HLA region.

The 21-hydroxylase gene is now termed CYP21. Its homologue is the pseudogene CYP21P (176).

Because CYP21P is a pseudogene, the lack of transcription renders it nonfunctional. The CYP21 is the active gene.

The CYP21 gene and the CYP21P pseudogene alternate with two genes called C4B and C4A, both of which encode for the fourth component (c4) of serum complement (176).

The close linkage between the 21-hydroxylase genes and HLA alleles allowed the study of 21-hydroxylase inheritance patterns in families through blood HLA typing (e.g., linkage of HLA-B14 was found in Ashkenazi Jews, Hispanics, and Italians) (177).

Prenatal Diagnosis and Treatment

Women with congenital and adult-onset forms of the disorder are at a significant risk for having affected infants, owing to the high frequency of 21-hydroxylase mutations in the general population. This presents an important rationale for screening hyperandrogenic women for this disorder when they anticipate childbearing. In families at risk for CAH and in instances where one partner expresses the congenital or adult onset form of the disease, first-trimester prenatal screening using chorionic villus sampling is advocated (176). The fetal DNA is used for specific amplification of the CYP21 gene using polymerase chain reaction (PCR) amplification (178). When the fetus is at risk for CAH, maternal dexamethasone treatment can suppress the fetal HPA axis and prevent genital virilization in affected females (179). The dose is 20 μg/kg in three divided doses administered as soon as pregnancy is recognized and no later than 9 weeks of gestation. This is done prior to performing chorionic villus sampling or amniocentesis in the second trimester. Dexamethasone crosses the placenta and suppresses ACTH in the fetus. If the fetus is determined to be an unaffected female or a male, treatment is discontinued. If the fetus is an affected female, dexamethasone therapy is continued.

The practice of prenatal dexamethasone treatment for women whose fetuses are at risk for CAH is controversial; seven of eight pregnancies will treated with dexamethasone unnecessarily, albeit briefly, to prevent one case of ambiguous genitalia. The efficacy and safety of prenatal dexamethasone treatment is not established, and long-term follow-up data on the offspring of treated pregnancies are lacking (180).

Numerous studies in experimental animal models showed that prenatal dexamethasone exposure could impair somatic growth, brain development, and blood pressure regulation. A human study of 40 fetuses as risk for CAH who were treated prenatally with dexamethasone to prevent virilization of affected females reported long-term effects on neuropsychological functions and scholastic performance (179, 181).

The 2010 Endocrine Society guidelines conclude that prenatal dexamethasone therapy should be pursued only through institutional review board’s approved protocols at centers capable of collecting sufficient outcome data (182).

Treatment of Adult-Onset Congenital Adrenal Hyperplasia

Many patients with congenital AOAH do not need treatment. Glucocorticoid treatment should be avoided in asymptomatic patients with AOAH because the potential adverse effects of glucocorticoids probably outweigh any benefits (180, 182).

Glucocorticoid therapy is recommended only to reduce hyperandrogenism for those with significant symptoms. Dexamethasone and antiandrogen drugs (both cross the placenta) should be used with caution and in conjunction with oral contraceptives in adolescent girls and young women with signs of virilization or irregular menses. When fertility is desired, ovulation induction might be necessary, and a glucocorticoid that does not cross the placenta (e.g., prednisolone or prednisone) should be used (179).

Many patients who are undiagnosed but who actually have AOAH are treated with therapies for ovarian hyperandrogenism and/or PCOS, with progestins for endometrial regulation, clomiphene or gonadotropins for ovulation induction, or progestins and antiandrogens for control or hirsutism. These therapies may be appropriate, as an alternative to glucocorticoid therapy, even when AOAH is recognized as the cause for the patient’s symptoms.

Androgen-Producing Ovarian Neoplasms

Ovarian neoplasms are the most frequent androgen-producing tumors. Granulose cell tumors constitute 1% to 2% of all ovarian tumors and occur mostly in adult women (in postmenopausal more frequently than in premenopausal women) (see Chapter 37). Usually associated with estrogen production, they are the most common functioning tumors in children and can lead to isosexual precocious puberty (202). Patients can present with vaginal bleeding caused by endometrial hyperplasia or endometrial cancer resulting from prolonged exposure to tumor-derived estrogen (203).

Stromal Hyperplasia and Stromal Hyperthecosis

Stromal hyperplasia is a nonneoplastic proliferation of ovarian stromal cells. Stromal hyperthecosis is defined as the presence of luteinized stromal cells at a distance from the follicles (211). Stromal hyperplasia, which is typically seen in patients between 60 and 80 years of age, may be associated with hyperandrogenism, endometrial carcinoma, obesity, hypertension, and glucose intolerance (211, 212). Hyperthecosis is seen in a mild form in older patients. In patients of reproductive age, hyperthecosis may demonstrate severe clinical manifestations of virilization, obesity, and hypertension (213). Hyperinsulinemia and glucose intolerance may occur in up to 90% of patients with hyperthecosis and may play a role in the etiology of stromal luteinization and hyperandrogenism (72). Hyperthecosis is found in many patients with HAIR-AN syndrome (hyperandrogenemia, insulin resistance, and acanthosis nigricans).

In patients with hyperthecosis, levels of ovarian androgens, including testosterone, DHT, and androstenedione, are increased, usually in the male range. The predominant estrogen, as in PCOS, is estrone, which is derived from peripheral aromatization. The E1-to-E2 ratio is increased. Unlike in PCOS, gonadotropin levels are normal (214). Ovarian with stromal hyperthecosis have variable sonographic appearances (215).

Wedge resection for the treatment of mild hyperthecosis was successful and resulted in resumption of ovulation and in a pregnancy (216). In cases of more severe hyperthecosis and high total testosterone levels, the ovulatory response to wedge resection is transient (214). In a study in which bilateral oophorectomy was used to control severe virilization, hypertension and glucose intolerance sometimes disappeared (217). When a GnRH agonist was use to treat patients with severe hyperthecosis, ovarian androgen production was dramatically suppressed (218).

Prolactin Disorders

Prolactin was first identified as a product of the anterior pituitary in 1933 (225). It is found in nearly every vertebrate species. Its presence in humans was long inferred by the association of the syndrome of amenorrhea and galactorrhea in the presence of pituitary macroadenomas, though it was not definitively identified as a human hormone until 1971. The specific activities of human prolactin (hPRL) were defined by the separation of its activity from growth hormone and subsequently by the development of radioimmunoassay (226, 228). Although the initiation and maintenance of lactation is the primary function of prolactin, many studies document roles for prolactin activity both within and beyond the reproductive system.

Prolactin Secretion

There are 199 amino acids within human prolactin, with a molecular weight (MW) of 23,000 D (Fig. 31.8). Although human growth hormone and placental lactogen have significant lactogenic activity, they have only a 16% and 13% amino acid sequence homology with prolactin, respectively. In the human genome, a single gene on chromosome 6 encodes prolactin. The prolactin gene (10kb) has five exons and four introns, and its transcription is regulated in the pituitary by a proximal promotor region and in extrapituitary locations by a more upstream promotor (229).

In the basal state three forms are released: a monomer, a dimer, and a multimeric species, called little, big, and big-big prolactin, respectively (230-232). The two larger species can be degraded to the monomeric form by reducing disulfide bonds (233). The proportions of each of these prolactin species vary with physiologic, pathologic, and hormonal stimulation (233-236). The heterogeneity of secreted forms remains an active area of research. Studies indicate that little prolactin (MW 23,000 D) constitutes more than 50% of all combined prolactin production and is most responsive to extrapituitary stimulation or suppression (233, 235, 236). Clinical assays for prolactin measure the little prolactin, and in all but extremely rare circumstances, these measures are sufficient to assess diseases of abnormal pituitary production of the hormone. Prolactin, and its relatives growth hormone and placental lactogen, do not require glycosylation for most of their primary activities, as is the case for the gonadotropins and TSH. Glycosylation forms are secreted, and glycosylation does affect the bioactivity and immunoreactivity of little prolactin (237-240). It appears that the glycosylated form is the predominant species secreted, but the most potent biologic form appears to be the 23,000-D nonglycosylated form of prolactin (239). Prolactin has over 300 known biological activities. Prolactin’s most recognized activities include those associated with reproduction (lactation, luteal function, reproductive behavior) and homeostasis (immune responsivity, osomoregulation, and angiogenesis) (241). Despite these many activities, the only recognized disorder associated with deficiency of prolactin secretion is inability to lactate.

Hyperprolacctinemia

Physiologic disturbances, pharmacologic agents, or markedly compromised renal function may cause elevations in prolactin levels, and transient elevations occur with acute stress or painful stimuli. The most common cause of elevated prolactin levels is likely pharmacologic; most patients using antipsychotic medications and many other patients using agents with antidopaminergic properties will exhibit moderately elevated prolactin levels. Drug-related and physiologic conditions resulting in hyperprolactinemia do not always require direct intervention to normalize prolactin levels.

Evaluation

Plasma levels of immunoreactive prolactin are 5 to 27 ng/mL throughout the normal menstrual cycle. Samples should not be drawn soon after the patient awakes or after procedures. Prolactin is secreted in a pulsatile fashion with a pulse frequency ranging from about 14 pulses per 24 hours in the late follicular phase to about 9 pulses per 24 hours in the late luteal phase. There also is a diurnal variation, with the lowest levels occurring n mid-morning. Levels rise 1 hour after the onset of sleep and continue on rise until peak values are reached between 5 and 7 a.m. (256, 257). The pulse amplitude of prolactin appears to increase from early to late follicular and luteal phases (258-260). Because of the variability of secretion and inherent limitations of radioimmunoassay, an elevated level should always be rechecked. This sample preferably is drawn midmorning and not after stress, previous venipuncture, breast stimulation, or physical examination, all of which transiently increase prolactin levels.

When prolactin levels are found to be elevated, hypothyroidism and medications should first be ruled out as a cause. Prolactin and TSH determinations are basic evaluations in infertile women. Infertile men with hypogenadism should be tested. Likewise, prolaction levels should be measured in the evaluation of amenorrhea, galactorrhea, hirsutism with amenorrhea, anovulatory bleeding, and delayed puberty (Fig. 31.9).

Physical Signs

Elevations in prolactin may cause amenorrhea, glactorrhea, both, or neither. Amenorrhea without galactorrhea is associated with hyperprolactinemia in approximately 15% of women (261-263). The cessation of normal ovulatory processes resulting from elevated prolactin levels is primarily caused by the suppressive effects of prolactin, via hypothalamic mediation, on GnRH pulsatile release (243, 261, 262, 264-272). In addition to causing a hypogonadotropic state, prolactin elevations may secondarily impair the mechanisms of ovulation by causing a reduction in granulose cell number and FSH binding, inhibition of granulose cell 17β-estradiol production by interfering with FSH action, and by causing inadequate luteinization and reduced luteal secretion of progesterone (273-278). Other etiologies for amenorrhea are detailed in Chapter 30.

Although isolated galactorrhea is considered indicative of hyperprolactinemia, prolactin levels are within the normal range in nearly 50% of such patients (279-281) (Fig.31.90). in these cases, whether caused by a prior transient episode of hyperprolactinemia or other unknown factors, the sensitivity of the breast to the lactotrophic stimulus engendered by normal prolactin levels is sufficient to result in galactorrhea. This situation is very similar to that observed in nursing mothers in whom milk secretion, once established, continues and even increases despite progressice normalization of prolactin levels. Repeat testing is occasionally helpful in detecting hyperprolactinemia. Approximately one-third of women with galactorrhea have normal menses. Conversely, hyperprolactinemia commonly occurs in the absence of galactorrhea (66%), which may result from inadequate estrogenic or progestational priming of the breast.

In patients with both galactorrhea and amenorrhea (including the syndromes desctibed and named by Forbes, Henneman, Griswold, and Albright in 1951,argonz and del Castilla in 1953, and Chiari and Frommel in 1985), approximately two-thirds will have hyperprolactinemia; in that group, approximately one-third will have a pituitary adenoma (282). In anovulatory women, 3% to 10% of women diagnosed with polycystic ovary disease have coesistent and usually modest hyperprolactinemia (283, 284) (Fig.31.10).

Prolactin and TSH levels should be measured in all patients with delayed puberty. Pituitary abnormalities, including craniopharyngiomas and adenomas, should be considered in all cases of delayed puberty accompanied by low levels of gonadotropins, regardless of whether prolactin levels are elevated. When prolactin-secreting pituitary adenomas are present, the condition of multiple endocrine neoplasia type 1 (MEN-1) syndrome (gastrinomas, insulinoma, parathyroid hyperplasia, and pituitary neoplasia) should be considered, although symptoms of pituitary adenoma are rarely the presenting symptom. Patients who have a pituitary adenoma and a family history of multiple adenomas warrant special attention (285). Prolactinomas are noted in approximately 20% of patients with MEN-1. The MEN-1 gene is localized to chromosome 11q13 and appears to act as a constitutive tumor suppressor gene. An inactivating mutation results in development of the tumor. It is thought that prolactin-secreting pituitary adenomas that occur in patients with MEN-1 may be more aggressive than sporadic cases (286).

When an elevated prolactin level is documented and medications or hypothyroidism as the underlying cause is excluded, knowledge of neuroanatomy and imaging techniques and their interpretation is essential to further evaluation (see Chapter 7). Pituitary hyperprolactinemia is most often caused by a microadenoma or associated with normal imaging findings. These patients can be reassured that the probable course of their condition is benign. Macroadenomas or juxtasellar lesions are less common and require more complex evaluation and treatment, including surgery, radiation, or both. Levels of TSH should be measured in all patients with hyperprolactinemia (Fig.31.9).

Imaging Techniques

In patients with larger microadenomas and macroadenomas, prolactin levels usually are higher than 100 ng/mL. However levels lower than 100 ng/mL may be associated with smaller microadenomas, macroadenomas that produce a “stalk section” effect and suprasellar tumors that may be missed on a “coned-down” view of the sella turcica. Modest elevations of prolactin can be associated with microadenomas or macroadenomas, nonlactotroph pituitary tumors, and other central nervous system abnormalities; thus, imaging of the pituitary gland must be considered when otherwise unexplained and persistent prolactin elevation is present. In patients with a clearly identifiable drug-induced or physiologic hyperprolactinemia, imaging is not necessary unless accompanied by symptoms suggesting a mass lesion (headache, visual field deficits). MRI with gadolinium enhancement of the sella and pituitary gland appears to provide the best anatomic detail (287). The cumulative radiation dose from multiple CT scans may cause cataracts, and the “coned-down” views or tomograms of the sella are very insensitive and expose the patient to radiation. For patients with hyperprolactinemia who desire future fertility, MRI is is indicated to differentiate a pituitary microadenoma from a macroadenoma and to identify other potential sellar-suprasellar masses. Although rare, when pregnancy-related complications of a pituirtary adenoma occur, they occur more frequently in the presence of macroadenomas.

In over 90% of untreated women, microadenomas do not enlarge over a 4-to-6-year period. The argument that medical therapy will prevent a microadenoma from growing is false. Although prolactin levels correlate with tumor size, both elevations and reductions in prolactin levels may occur without any change in tumor size. If during follow-up a prolactin level rises significantly or central nervous system symptoms (headache, visual changes) are noted, repeat imaging may be indicated. Treatment is discussed below.

Hypothalamic Disorders

Dopamine was the first of many substances whose production was demonstrated in the arcuate nucleus. Dopamine-releasing neurons innervate the external zone of the median eminence. When released into the hypophyseal portal system, dopamine inhibits prolactin release in the anterior pituitary. Lesions that disrupt dopamine release can result in hyperprolactinemia. Such lesions may arise from the suprasellar area, pituitary gland, and infundibular stalk, and from adjacent bone, brain, cranial nerves, dura, leptomeninges, nasopharynx, and vessels. Numerous pathologic entities and physiologic conditions in the hypothalamic-pituitary region can disrupt dopamine release and cause hyperprolactinemia.

Pituitary Disorders

Microadenoma

In over one-third of women with hyperprolactinemia, a radiologic abnormality consistent with a microadenoma (<1 cm) is found. Release of pituitary stem cell growth inhibition via activation or loss-of-function mutations results in cell cycle dysregulation and is critical to the development of pituitary microadenomas and macroanenomas. Microadenomas are monoclonal in origin. Genetic mutations are thought to release stem cell growth inhibitors and result in autonomous anterior pituitary hormone production, secretion, and cell proliferation. Additional anatomic factors that may contribute to adenoma formation include reduced dopamine concentrations in the hypophyseal portal system and vascular isolation of the tumor or both. Recently, the heparin-binding secretory-transforming (HST) gene was noted in a variety of cancers and in prolactinomas (288). Patients with microadenomas can be reassured of a probable benign course, and many of these lesions exhibit gradual spontaneous regression (

Both microadenomas and macroadenomas are monoclonal in origin. Pituitary prolactinomas and lactotrope adenomas are sparsely or densely granulated histologically. The sparsely granulated lactotrope adenomas have trabecular, papillary,or solid patterns. Calcification of these tumors may take the form of a psammoma body or a pituitary stone. Densely granulated lactotrope adenomas are strongly acidophilic tumors and appear to be more aggressive than sparsely granulated lactotrope adenomas. Unusual acidophil stem cell adenomas can be associated with hyperprolactinemia, with some clinical or biochemical evidence of growth hormone excess.

Microadenomas rarely progress to macroadenomas. Six large series of patients with microadenomas reveal that, with no treatment, the risk of progression for microadenoma to a macroadenoma is only 7% (291). Treatments include expectant, medical, or, rarely, surgical therapy. All affected women should be advised to notify their physicians of chronic headaches, visual disturbances (particularly tunnel vision consistent with bitemporal hemianopsia), and extraocular muscle palsies. Formal visual field testing is rarely helpful, unless imaging suggests compression of the optic nerves.

Autopsy and radiographic series reveal that 14.4% to 22.5% of the US population harbor microadenomas, and approximately 25% to 40% stain positively for prolactin (292). Clinically significant pituitary tumors requiring some type of intervention affect only 14 per 100,000 individuals (292).

Expectant Management 

In women who do not desire fertility, expectant management can be used for both microandnomas and hyperprolactinemia  without an adenoma while menstrual function remains intact. Hyperprolactinemia-induced estrogen deficiency, rather than prolactin itself, is the major factor in the development of osteopenia Therefore, estrogen replacement with typical hormone replacement regimens or hormonal contraceptives is indicated for patients with amenorrhea or irregular menses. Patients with drug-induced hyperprolactinemia can be managed expectantly with attention to the risks of osteoporosis. In the absence of symptoms of pituitary enlargement, imaging may be repeated in 12 months, and if prolactin levels remain stable, less frequently thereafter, to assess further growth of the microadenoma.

Medical Treatment

Ergot alkaloids are the mainstay of therapy. In 1985, bromocriptine was approved for use in the United States to treat hyperprolactinemia caused by a pituitary adenoma. These agents act as strong dopamine agonists, thus decreasing prolactin levels. Effects on prolactin levels occur within hours, and lesion size may decrease within 1 or 2 weeks. Bromocriptine decreases prolactin synthesis, DNA synthesis, cell multiplication, and overall size of prolactinomas, bromocriptine treatment results in normal prolactin blood levels or return of ovulatory menses in 80% to 90% of patients.

Because ergot alkaloids, like bromocriptine, are excreted via the biliary tree, caution is required when using it in the presence of liver disease. The major adverse effects include nausea, headaches, hypotension, dizziness, fatigue and drowsiness, omitting, headaches, nasal congestion, and constipation. Many patients tolerate bromocriptine when the dose is increased gradually, by 1.25 mg (one-half tablet) daily each week until prolactin levels are normal or a dose of 2.5 mg twice daily is reached. A proposed regimen is as follows: one-half tablet every evening (1.25 mg) for 1 week, one-half tablet morning and evening (1.25 mg)  during the second week, one-half tablet in the morning (1.25 mg) and a full tablet every evening (2.5 mg) during the third week, and one tablet every morning and every evening during the fourth week and thereafter (2.5 mg twice a day). The lowest dose that maintains the prolactin level in the normal range is continued (1.25 mg twice daily often is sufficient to normalize prolactin levels in individuals with levels less than 100 ng/dL. Pharmacokinetic studies show peak serum levels occur 3 hours after an oral dose, with a nadir at 7 hours. Because little detectable bromocriptine is in the serum by 11 to 14 hours, twice-a-day administration is required. Prolactin levels can be checked soon (6 to 24 hours) after the last dose.

One rare, but notable, adverse effect of bromocriptine is a psychotic reaction. Symptoms include auditory hallucinations, delusional ideas, and changes in mood that quickly resolve after discontinuation of the during .

Many investigators report no difference in fibrosis, calcification, prolactin immunoreactivity, or the surgical success in patients pretreated with bromocriptine compared to those not receiving bromocriptine (.

An alternative to oral administration is the vaginal administration or bromocriptine tablets, which is well tolerated, and actually results in increased pharmacokinetic measures . Cabergoline, another ergot alkaloid, has a very long half-life and can be given orally twice per week. Its long duration of action is attributable to slow elimination by pituitary tumor tissue, high affinity binding to pituitary dopamine receptors, and extensive enterohepatic recirculation.

Cabergoline, which appears to be as effective as bromocriptine in lowering prolactin levels and in reducing tumor size, has substantially fewer adverse effects than bromocriptine. Very rarely, patients experience nausea and vomiting or dizziness with cabergoline; they may be treated with intravaginal cabergoline as with bromocriptine. A gradually increasing dosage helps avoid the side effects on nausea, vomiting, and dizliness. Cabergoline at 0.25 mg twice per week is usually adequate for hyperprolactinemia with values less than 100 ng/mL. If required to normalize prolactin levels, the dosage can be increase by 0.25 mg per dose on a weekly basis to a maximum of 1 mg twice weekly.

Recent studies reveal an increased risk of cardiac valve regurgitation in patients with Parkinson disease who were treated with high doses of cabergoline or pergolide but not with bromocriptine . Higher doses and a longer duration of therapy were associated with a higher risk of valvulopathy. It is postulated that 5HT2b-receptor stimulation leads to fibromyoblast proliferation A recent cross-sectional study showed a higher rate of asymptomatic tricuspid regurgitation among cabergoline-treated patients compared to untreated patients with newly diagnosed prolactinomas as well as normal controls  

The demonstrated relative safety of bromocriptine in reproductive-aged women and during more than 2,500 pregnancies suggests bromocriptine is the first choice for hyperprolactinemia and moicro-and macrodenomas 

When bromocriptine or cabergoline cannot be used, other medications such as pergolide or metergoline may be used. In patients with a microadenoma who are receiving bromocriptine therapy, a repeat MRI scan may be performed 6 to 12 months after prolactin levelsare normal, if indicated. Further MRI scans should be performed if new symptons appear.

Discontinuation of bromocriptine therapy after 2 to 3 years may be attempted in a select group of patients who have maintained normoprolactinemia while on therapy. In a retrospective series of 131 patients treated with bromocriptine for a median of 47 months, normoprolactinemia was sustained in 21% at a median follow-up of 44 months after treatment discontinuation . Discontinuation of cabergoline therapy was successful in patients treated for 3 to 4 years who maintained normoprolactinemia (304). In cabergoline discontinuers who met stringent inclusion criteria, a recurrence rate of 64% was noted (305). A recent meta-analysis involving 743 patients noted sustained normoprolactinemia in only a minority of patients (21%) after discontinuation. Patients with 2 years or more of therapy before discontinuation and no demonstrable tumor visible on MRI had the highest chance of persistent normoprolactinemia . Recurrence rates are higher for macroadenomas (as compared to microadenomas or hyperprolactinemia without adenoma) after cessation of bromocriptine or cabergoline, warranting close follow-up with serum prolactin and MRI after cessation or therapy. In patients with macroadenomas, withdrawal of therapy should proceed with caution, as rapid tumor reexpansion may occur.

Macroadenomas

Macroadenomas are pituitary tumors that are larger than 1 cm in size. Bromocriptine is the best initial and potentially long-term treatment option, but transsphenoidal surgery may be required. High-dose cabergoline therapy was used in bromocriptine resistant or intolerant macroadenoma patients with success; however, cautions remain regarding the development of cardiac valve abnormalities 

Evaluation for pituitary hormone deficiencies may be indicated. Symptoms of macroadenoma enlargement include severe headaches, visual field changes, and, rarely, diabetes insipidus and blindness. After prolactin has reached normal levels following ergot alkaloid treatment, a repeat MRI is indicated within 6 months to document shrinkage or stabilization of the size of the macroadenoma. This examination may be performed earlier if new symptoms develop or if there is no improvement in previously noted symptoms.

Medical Treatment        Treatment with bromocriptine decreases prolactin levels and the size of macroadenomas; nearly one-half show a 50% reduction in size, and another one-fourth show a 33% reduction after 6 months of therapy. Because tumor regrowth occurs in more than 60% of cases after discontinuation of bromocriptine therapy, long-term therapy is usually required.

After stabilization of tumor size is documented, the MRI scan is repeated 6 months later and, is stable, yearly for several years. This examination may be performed earlier if new symptoms develop or if there is no improvement in symptoms. Serum prolactin levels are measured every 6 months. Because tumors may enlarge despite normalized prolactin values, a reevaluation of symptoms at regular intervals (6 months) is prudent. Normalized prolactin levels or resumption of menses should not be taken as absolute proof of tumor response to treatment .

Surgical Intervention Tumors that are unresponsive to bromocriptine or that cause persistent visual field loss require surgical intervention. Some neurosurgeons have noted that a short (2-to 6 weeks) preoperative course of bromocriptine increases the efficacy of surgery in patients with larger adenomas  Unfortunately, despite surgical resection, recurrence of hyperprolactinemia and tumor growth is common; complications of surgery include cerebral carotid artery injury, diabetes insipidus, meningitis, nasal septal perforation, partial or panhypopituitarism, spinal fluid rhinorrhea, and third nerve palsy. Periodic MRI scanning after surgery is indicated, particularly in patients with recurrent hyperprolactinemia.

Metabolic Dusfunction and Hyperprolactinemia

Occasionally, patients with hypothyroidism exhibit hyperprolactinemia with remarkable pituitary enlargement caused by thyrotroph hyperplasia. These patients respond to thyroid replacement therapy with reduction in pituitary enlargement and normalization of prolactin levels .

Hyperprolactinemia occurs in 20% to 75% of women with chronic renal failure. Prolactin levels are not normalized through hemodialysis but are normalized after transplantation . Occasionally, women with hyperandrogenemia also have hyperprolactinemia. Elevated prolactin levels may alter adrenal function by enhancing the release of adrenal androgens such as DHEAS 

Drug-Induced Hyperprolactinemia

Numerous drugs interfere with dopamine secretion and can be responsible for hyperprolactinemia and its attendant symptoms If medication can be discontinued, resolution of hyperprolactinemia is uniformly prompt. If not, endocrine management should be directed at estrogen replacement and normalization of menses for those with disturbed or absent ovulation. Treatment with dopamine agonists may be utilized if ovulation is desired and the drug-inducing hyperprolactinemia cannot be discontinued.

Use of Estrogen in Hyperprolactinemia

In rodents, pituitary prolactin-secretin adenomas occur with high-dose estrogen administration  Elevated levels of estrogen, as found in pregnancy, are responsible for hypertrophy and hyperplasia of lactotrophic cells and account for the progressive increase in prolactin levels in normal pregnancy. The increase in prolactin during pregnancy is physiologic and reversible; adenomas are not fostered by the hyperestrogemia of pregnancy, pregnancy may have a favorable influence on preexisting prolcatinomas.  Estrogen administrationis not associated with clinical, biochemical, or radiologic evidence of growth of pituitary microadenomas or the progression of idiopathic hyperprolactinemia to an adenoma status (317, 320). For these reasons, estrogen replacement or OC use is appropriate for hypoestrogenic patients with hyperprolactinemia secondary to microadenoma or hyperplasia.

Monitoring Pituitary Adenomas During Pregnancy

Prolactin-secreting microadenomas rarely create complications during pregnancy. Monitoring of patients with serial gross visual field examinations and funduscopic examination is recommended. If persistent headaches, visual field deficits, or visual or funduscopic changes occur, MRI scanning is advisable.

Because serum prolactin levels progressively rise throughout pregnancy, prolactin measurements are rarely of value.

For those women who become pregnant while taking bromocriptine to treat a return of spontaneous ovulations, discontinuation of bromocriptine is recommended. This does not preclude subsequent use of bromocriptine during the pregnancy to treat symptoms (visual field defects, headaches) that arise from further enlargement of the microadenoma . Bromocriptine did not exhibit teratogenicity in animals, and observational data do not suggest harm to pregnancy or fetus in humans.

Pregnant women with previous transsphenoidal surgery for microadenomas or macroadenomas may be monitored with monthly Glodman perimetry visual field testing. Periodic MRI scanning may be necessary in women with symptoms or visual changes. Breastfeeding is not contraindicated in the presence of microadenomas . The use of bromocriptine and presumably other dopaminergic agents that may cause blood pressure elevation during the postpartum period is contraindicated 

Thyroid Function

Measurements of free serum T₄ and T₃ are complicated by the low levels of free hormone in systemic circulation, with only 0.02% to 0.03% of T₄ and 0.2% to 0.3% of T₃ circulating in the unbound state (340). Of the T₄ and T₃ in circulation, approximately 70% to 75% is bound to TBG, 10% to 15% attached to prealbumin, 10% to 15% bound to albumin, and a minor fraction (<5%) is bound to lipoprotein (340, 341). Total thyroid measurements are dependent on levels of TBG, which are variable and affected by many conditions such as pregnancy, oral contraceptive pill use, estrogen therapy, hepatitis, and genetic abnormalities of TBG. Thus, assays for the measurement of free T₄ and T₃ are more clinically relevant than measuring total thyroid hormone levels.

There are many different laboratory techniques to measure estimated free serum T₄ and T₃. These methods invariably measure a portion of free hormone that is dissociated from the in vivo protein bound moiety. This is of little clinical significance assuming the same proportions are measured for all assays and considered in the calibration of the assay (342). The T₃ resin uptake test in an example of one laboratory method used to estimate free T₄ in the serum. The T₃ resin uptake (T₃ RU) determines the fractional binding or radiolabeled T₃, which is added to a serum sample in the presence of a resin that competes with TBG for T₃ binding. The binding capacity of TBG in the sample is inversely proportional to the amount of labeled T₃ bound to the artificial resin. Therefore, a low T₃ resin uptake indicates high TBG T₃ receptor site availability and implies high circulating TBG levels.

The free T₄ index (FTI) is obtained by multiplying the serum T₄ concentration by the T₃ resin uptake percentage, yielding an indirect estimate of the levels of free T₄:

T₃ RU% X T₄ total= free T₄ index.

A high T₃ RU percentage indicates reduced TBG receptor site availability and high free T₄ index and thus hyperthyroidism, whereas a low T₃ resin uptake percentage is a result of increased TBG receptor site binding and thus hypothyroidism. Equilibrium dialysis and ultrafiltration techniques may be used to determine the free T4 directly.  Free T4 and T3 may also be determined by radioimmunoassay. Most available laboratory methods used for determining estimations or free T4 are able to correct for moderate variations in serum TBG but are prone to error in the setting of large variations of serum TBG, when endogenous T4 antibodies are present, and in the setting of inherent albumin abnormalities (340).

Because most disorders of hyperthyroidism and hypothyroidism are related to dysfunction of the thyroid gland and TSH levels are sensitive to excessive or deficient levels of circulating thyroid hormone, TSH levels are used to screen for these disorders. Current  thyrotropin or TSH sandwich immunoassays are extremely sensitive and capable of differentiating low-normal from pathologic or iatrogenically subnormal values and elevations. TSH measurements provide the best way to screen for thyroid dysfunction and accurately predict thyroid hormone dysfunction in about 80% of cases (343). Reference values for TSH are traditionally based on the central 95% of values for healthy individuals, and some controversy exists regarding the upper limit of normal. Values in the upper limit of normal may predict future thyroid disease . In a longitudinal study, women with positive thyroid antibodies (TPOAbs or TgAbs), the prevalence of hypothyroidism at follow-up was 12.0% (3.0% to 21.0%; 95% CI) when baseline TSH was 2.5 mU/L or less, 55.2% (37.1%-73.3%) for TSH between 2.5 and 4.0mU/L, and 85.7% (74.1%-97.3%) for TSH above 4.0 mU/L (345). Physicians ordering thyrotropin values should be aware of their limitations in the setting or acute illness, central hypothyroidism, the presence of heterophile antibodies, and TSH autoantibodies. In the setting of heterophile antibodies or TSH autoantibodies, TSH values will be falsely elevated . In cases of central hypothyroidism, decreased sialylation of TSH results in a longer half-life and a reduction in bioactivity . TSH levels may be elevated or normal when the patient remains clinically hypothyroid in states of central hypothyroidism, and successful treatment is often associated with low or undetectable TSH levels.

Table 31.10 Thyroid Autoantigens
Antigen	Location	Function
Thyroglobulin (Tg)	Thyroid	Thyroid hormone storage
Thyroid peroxidase (TPO) (microsomal antigen)	Thyroid	Transduction of signal from TSH
TSH receptor (TSHR)	Thyroid, lymphocytes, fibroblasts, adipocytes (including retro-orbital), and cancers	Transduction of signal from TSH
Na+/l- symporter (NIS)	Thyroid, breast, salivary or lacrimal gland, gastric or colonic mucosa, thymus, pancreas	ATP-driven uptake of l- along with Na+

TSH, thyroid-stimulating hormone; ATP, adenosine triphosphate

Immunologic Abnormalities

Many antigen-antibody reactions affecting the thyroid gland can be detected. Antibodies to TgAb, the TSH receptor (TSHRAb), TPOAb, the sodium iodine symporter (NISAb), and to thyroid hormone were identified and implicated in autoimmune thyroid disease states ..Antibody production to thyroglobulin depends on a breach in normal immune surveillance . 

Antithyroglobulin antibodies are predominantly in the noncomplement fixing, polycolonal, immunoglobulin-G (IgG) class. Antithyroglobulin antibodies are found in 35% to 60% of patients with hypothyroid autoimmune thyroiditis, 12% to 30% of patients with Graves disease, and 3% of the general population Antithyroglobulin antibodies are associated with acute thyroiditis, nontoxic goiter, and thyroid cancer (348).

Previously referred to as antimicrosomal antibodies, TPO antibodies are directed against thyroid peroxidase and are found in Hashimoto thyroiditis, Graves disease, and postpartum thyroiditis. The antibodies produced are characteristically cytotoxic, complement-fixing IgG antibodies. In patients with thyroid autoantibodies, 99% will have positive anti-TPO antibodies, whereas only 36% will have positive antithyroglobulin antibodies, making anti-TPO a more sensitive test for autoimmune thyroid disease (353). Anti-TPO antibodies are present in 80% to 90% of patients with hypothyroid autoimmune thyroiditis, 45% to 80% of patients with Graves disease, and 10% to 15% of the general population (352- 354). These antibodies can cause artifact in the measurement of thyroid hormone levels. Antithyroid peroxidase antibodies are used clinically in

Table 31.11 Prevalence of Thyroid Autoantibodies and their Role in Immunopathology
Antibody	General Population	Hypothyroid Autoimmune Thyroiditis	Graves Disease
Antithyroglobulin (TgAb)	3%	35%-60%	12%-30%
Antimicrosomal thyroid peroxidase (TPOAb)	10%-15%	80%-99%	45%-80%
Anti-TSH receptor (TSHRAb)	1%-2%	6%-60%	70%-100%
Anti-Na/l symporter (NISAb)	0%	25%	20%

TSH, thyroid-stimulating hormone.

Table 31.12 Nomenclalure of Anti-TSH Receptor Antibodies
Abbreviation	Term	Assay Used	Refers To
LATS	Long-acting thyroid stimulator	In vivo assay of stimulation of mouse thyroid	Original description of serum molecule able to stimulate mouse thyroid; no longer used
TSHRAb, TRAb	TSHR antibodies	Competitive and functional  assays described below	All antibodies recognizing the TSH receptor (includes TBII (competitive), and TSI, TBI and TNI (functional) based on assay method
TBII	TSHR-binding inhibitory immunoglobulin	Competitive binding assays with TSH	Antibodies able to compete with TSH for TSH receptor binding irrespective of biologic activity
TSI (also TSAb)	TSHR-stimulating immunoglobulins	Competitive and functional bioassays of TSH receptor activation	Antibodies able to block TSH receptor binding, induce cAMP production and nonclassical signaling cascades
TBI (also TSBAb, TSHBAb	TSHR stimulation-blocking antibodies	Functional bioassays of TSH receptor activation	Antibodies able to block TSH receptor binding, induce cAMP production with +/- effects on nonclassical cascades
TNI	TSHR nonbinding immunoglobulin	Binding and functional assays	No TSH binding, no effect on cAMP levels and variable effects on nonclassical cascades

TSH, thyroid-stimulating hormone.

 the diagnosis of Graves disease, the diagnosis of chronic autoimmune thyroiditis, in conjunction with TSH testing as a means to predict future hypothyroidism in subclinical hypothyroidism, and to assist in the diagnosis of autoimmune thyroiditis in euthyroid patients with goiter or nodules 

Autoimmune Thyroid Disease

The most common thyroid abnormalities in women, autoimmune thyroid disorders, represent the combined effects of the multiple thyroid autoantibodies. The various antigen-antibody reactions result in the wide clinical spectrum of these disorders. Transplacental transmission of some of these immunoglobulins may affect thyroid function in the fetus. The presence of autoimmune thyroid disorders, particularly Graves disease, is associated with other autoimmune conditions: Hashimoto thyroiditis, Addison disease, ovarian failure, rheumatoid arthritis, Sjogren syndrome, diabetes mellitus (type 1), vitiligo, pernicious anemia, myasthenia gravis, and idiopathic thrombocytopenic purpura. Other factors that are associated with the development of autoimmune thyroid disorders include low birth weight, iodine excess and deficiency, selenium deficiency, parity, oral contraceptive pill use, reproductive age span, fetal microchimerism, stress, seasonal variation, allergy, smoking, radiation damage to the thyroid, and viral and bacterial infections (366).

Recommendations for Testing and Treatment

Overt and subclinical hypothyroidism are defined as an elevated TSH with a low T₄ and an elevated TSH and normal T₄, respectively, using appropriate patient ranges (nonpregnant and pregnant). A number of professional organizations published various recommendations for thyroid function assessment via a TSH in women. Because of the long interval from development of disease to diagnosis, the nonspecific nature of symptoms, and the potential adverse neonatal and maternal outcomes associated with untreated hypothyroidism in pregnancy, the American Association of Clinical Endocrinologists (AACE) recommended screening women prior to conceiving or at the first prenatal appointment . The AACE also recommended screening for the presence of hypothyroidism in patients with type 1 diabetes mellitus (threefold increased risk of postpartum thyroid dysfunction and 33% prevalence overall), patients taking lithium therapy (35% prevalence), and consideration of testing in patients presenting with infertility (>12% prevalence) or depression (10% to 12% prevalence), as these populations are at an increased risk of hypothyroidism (368). A screening TSH was recommended in women starting at the age of 50 because of the increased prevalence of hypothyroidism in this population (369). Thyroid function testing at 6-month intervals was recommended for patients taking amiodarone, as hyperthyroidism or hypothyroidism occurs in 14% to 18% of these patients (368). Any woman with a history of postpartum thyroiditis should be offered annual surveillance of thyroid function, as 50% of these patients will develop hypothyroidism within 7 years of diagnosis (370). Because there is a high prevalence of hypothyroidism in women with Turner and Down syndrome, an annual check of thyroid function is recommended for these patients 

Alternatively, the Endocrine Society’s clinical practice guidelines regarding the management of thyroid dysfunction during pregnancy and postpartum recommends targeted screening for the following individuals: history of thyroid disorder, family history of thyroid disease, goiter, thyroid autoantibodies, clinical signs or symptoms of thyroid disease, autoimmune disorders, infertility, head and/or neck radiation, and preterm deliver. The American Congress of Obstetricians and Gynecologists accepted these recommendations for TSH testing (374). Because of the (i) potentially significant neurologic affects on the fetus and other adverse pregnancy events; (ii) physiologic rise in TBG and the TSH-like activity of hCG in pregnancy, and (iii) potential for the targeted screening groups to have overt or subclinical hypothyroidism defined by the reference ranges for pregnancy (TSH <2.5, 3.1 and 3.5 μIU/mL for the first, second, and third trimesters, respectively), targeted maternal testing for hypothyroidism is encouraged. The targeted screening protocol allows that 30% of subclinical hypothyroidism cases may be missed. According to these recommendations, preconceptionally diagnosed hypothyroid women (overt or subclinical) should have their T₄ dosage adjusted such that the TSH value is less than 2.5 μIU/mL before pregnancy. The T₄ dosage in women already on replacement will routinely require a dose escalation (30% to 50%) at 4 to 6 weeks gestation in order to maintain a TSH value less than 2.5μIU/mL. Pregnant women with overt hypothyroidism should be normalized as rapidly as possible to maintain TSH at less than 2.5 and 3 μIU/mL in the first, second, and third trimesters, respectively. Euthyroid women with thyroid autoantibodies are at risk of hypothyroidism and should have TSH careening in each trimester. After delivery, hypothyroid women need a reduction in T₄ dosage used pregnancy. Because subclinical hypothyroidism is associated with adverse outcomes for mother and the fetus, T₄ replacement is recommend.

Hashimoto Thyroiditis

Hashimoto thyroiditis, or chronic lymphocytic thyroiditis, was firstdescribed in 1912 by Dr. Hakaru Hashimoto. Hashimoto thyroiditis can manifest as hyperthyroidism, hypothyroidism, euthyroid goite, or diffuse goiter. High levels of antimicrosomal and antithyroglobulin antibody are usually present, and TSHRAb may be present .. Typically, glandular hypertrophy is found, but atrophic forms are also present. Three classic types of autoimmune injure are found in Hashimoto thyroiditis: (i) complement-mediated cytotoxicity, (ii) antibody-dependent cell-mediated cytotoxicity, and (iii) stimulation or blockade of hormone receptors, which result in hypo-or hyperfunction or growth (Fig.31.11).

The histologic picture of Hashimoto thyroiditis includes cellular hyperplasia, disruption or follicular cells, and infiltration of the gland y lymphocytes, monocytes, and plasma cells. Occasionally, adjacent lymphadenopathy may be noted. Some epithelial cells are enlarged and demonstrate oxyphilic changes in the cytoplasm (Askanazy cells or Hurthle cells, which are not specific to this disorder). The interstitial cells show fibrosis and lymphocytic infiltration. Graves disease and Hashimoto thyroiditis may cause very similar histologic findings manifested by a similar mechanism of injury.

Treatment

Thyroxine replacement is initiated in patients with clinically overt hypothyroidism or subclinical hypothyroidism with a goiter. Regression of gland size usually does not occur, but treatment often prevents further growth of the thyroid gland. Treatment is recommended for patients with subclinical hypothyroidism in the setting or a TSH greater than 10mIU/L on repeat measurements, pregnant patients, a strong habit of tobacco use, signs or symptoms associated with thyroid failure, or patients with severe hyperlipidemia   All pregnant patients with an elevated TSH level should be treated with levothyroxine. Treatment does not slow progression of the disease. The initial dosage of levothyroxine may be as little as 12.5 μg per day up to up to a full replacement dose. The mean replacement dosage of levothyroxine is 1.6 μg/kg or body weight per day, although the dosage varies greatly between patients (368). Aluminum hydroxide (antacids), cholestyramine, iron, calcium, and sucralfate may interfere with absorption. Rifampin and sertraline hydrochloride may accelerate the metabolism of levothyroxine is nearly 7 days; therefore, nearly 6 weeks of treatment are necessary before the effects of a dosage change can be evaluated.

Hypothyroidism appears to be associated with decreased fertility resulting from disruption in ovulation, and thyroid autoimmune disease is associated with an increased risk of pregnancy loss with or without overt thyroid dysfunction  A meta-analysis of case-control and longitudinal studies performed since 1990 reveals a possible association between miscarriage and thyroid antibodies wi6th an odds ratio of 2.73 (95% CI, 2.20 – 3.40). This association may be explained by a heightened autoimmune state affecting the fetal allograft or a slightly higher age of women with antibodies compared with those without antibodies (0.7 + 1 year, p <.001) (342). Studies suggest that early subclinical hypothyroidism may be associated with menorrhagia .

Severe primary hypothyroidism is associated with menstrual irregularities in 23% of women, with oligomenorrhea being the most common . Reproductive dysfunction in hypothyroidism may be caused by a decrease in the binding activity of sex hormone-binding globulin, resulting in increased estradiol and free testosterone and from hyperprolactinemia (382). The increase in prolactiin levels is the result of enhanced sensitivity of the prolactin-secreting cells to TRH (with elevated TRH seen in primary hypothyroidism) and defective dopamine turnover resulting in hyperprolactinemia .Hyperprolactinemia-induced luteal phase defects are associated with less severe forms of hypothyroidism . Replacement therapy appears to reverse the hyperprolactinemia and correct ovulatory defects .

Combined thyroxine and triiodothyronine therapy is no more effective than thyroxine therapy alone, and patients with hypothyroidism should be treated with thyroxine alone (392). Treatment should target normalizing TSH values, and a daily dose of 0.012 mg up to a full replacement dose of levothyroxine (1.6 μg/kg of body weight per day) may be required with dosage dependent on the patient’s weight, age, cardiac status, and duration and severity of hypothyroidism .

Clinical Characteristics and Diagnosis

The class is triad in Graves disease consists of exophthalmos, goiter, and hyperthyroidism. The symptoms associated with Graves disease include frequent bowel movements, heat intolerance, irritability, nervousness, heart palpitations, impaired fertility, vision changes, sleep disturbances, tremor, weight loss, and lower extremity swelling. Physical findings may include lid lag, notender thyroid enlargement (two to four times normal), onycholysis, dependent lower extremity edema, palmar erythema, proptosis, staring gaze, and thick skin. A cervical venous bruit and tachycardia may be noted. The tachycardia does not respond to increased vagal tone produced with a Valsalva maneuver. Severe cases may demonstrate acropachy, chemosis, clubbing, dermopathy, exophthalmos with ophthalmoplegia, follicular conjunctivitis, pretibial, myxedema, and vision loss.

Approximately 40% of patients with new onset of Graves disease and many of those previously treated have elevated T₃ and normal T₄ levels. Abnormal T₄ or T₃ results are often caused by protein binding changes rather than altered thyroid function; therefore assessment of free T₄ and free T₃ is indicated in conjunction with TSH. In Graves, the TSH levels are suppressed, and levels may remain undetectable for some time even after the initiation of treatment. Thyroid autoantibodies, including TSI, may be useful during pregnancy to more accurately predict fetal risk of thyrotoxicosis . Autonomously functioning benign thyroid neoplasms that exhibit

Table 31.14 Potential Causes of Hyperthyroidism

Factitious hyperthyroidism

Graves disease

Metastatic follicular cancer

Pituitary hyperthyroidism

Postpartum thyroiditis

Silent hyperthyroidism (low radioiodine uptake)

Struma ovarii

Subacute thyroiditis

Toxic multinodular goiter

Toxic nodule

Tumors secreting human chorionic gonadotropin (molar pregnancy, choriocarcinoma)

a similar clinical picture include toxic adenomas and toxic multinodular goiter. A radioactive iodine uptake thyroid scan may help differentiate these two conditions from Graves disease. Rare conditions resulting in thyrotoxicosis include metastatic thyroid carcinoma causing thyrotoxicosis, amiodarone induced thyrotoxicosis, iodine induced thyrotoxicosis, postpartum thyroiditis, a TSH-secreting pituitary adenoma, an hCG- secreting chofiocarcinoma, struma ovarii, and “de Quervan’s” or sbuacute thyroiditis Factitious ingestion of thyroxine or desiccated thyroid should be considered in patients with eating disorders. Patients with thyrotoxicosis factitia demonstrate elevated T₃ and T₄ suppressed TSH, and a low serum thyroglobulin level, whereas other causes of thyroiditis and thyrotoxicosis demonstrate high levels of thyroglobulin. Potential causes of hyperthyroidism are listed in Table31.4.

Antithyroid  Drugs

Antithyroid drugs of the thioamide class include propylthiouracil (PTU) and methimazole. Low doses of either agent block the secondary coupling reactions that form T₃ and T₄ from MIT and DIT. At higher doses, they also block iodination of tyrosy1 residues in thyroglobulin, Propylthiouracil additionally blocks the peripheral conversion of T4 to T3. Approximately one-third of patients treated by this approach alone go into remission and become euthyroid 

Hyperthyroidism in Gestational Trophoblastic Disease and Hyperemesis Gravidarum

Because of the weak TSH-like activity of hCG, conditions with levels of hCG, such as molar pregnancy, may be associated with biochemical and clinical hyperthyroidism. Symptoms regress with removal or the abnormal trophoblastic  tissue and resolution of elevated levels of hCG. In a similar fashion, when hyperemesis gravidarum is associated with high levels of hCG, mile biochemical and clinical features of hyperthyroidism may be seen .

Thyroid Function in Pregnancy

Physicians should be aware of the changes in thyroid physiology during pregnancy. Pregnancy is associated with reversible changes in thyroid physiology that should be noted before diagnosing thyroid abnormalities (see Fig.31.12 for pregnancy associated changes in TBG, total T_4, hCG, TSH, and free T₄) . Women with a history of hypothyroidism often require increased thyroxine replacement during pregnancy, and patients should have thyroid function tests performed at the first prenatal visit and during each trimester thereafter. Evidence suggests that optimal fetal and infant neurodevelopmental outcomes may require careful titration of replacement thyroxine that meets the frequently increased requirements of pregnancy.

Reproductive Effects of Hyperthyroidism

High levels of TSAb (TSI) in women with Graves disease are associated with fetal-neonatal hyperthyroidism . Despite both the inhibition and elevation of gonadotropins seen in thyrotosicosis, most women remain ovulatory and fertile . Severe thyrotoxicosis can result in weight loss, menstrual cycle irregularities, and amenorrhea. An increased risk of spontaneous abortion is noted in women with thyrotoxicosis. An increased incidence of congenital anomalies, particularly choanal atresia and possibly aplasia cutis, can occur in the offspring of women treated with methimazole 

Autoimmune hyperthyroid Graves disease may improve spontaneously, in which case antithyroid drug therapy may be reduced or stopped. TSHRAb production may persist for several years after radical radioactive iodine therapy or surgical treatment for hyperthyroid Graves disease. In this circumstance, there is a risk of exposing a fetus to TSHRAb. Fetal-neonatal hyperthyroidism is observed in 2% to 10% of pregnancies occurring in mothers with a current or previous diagnosis of Graves disease, secondary to the transplacental passageof maternal TSHRAb. This is a serious condition with a 16% neonatal mortality rate and a risk of intrauterine fetal death, stillbirth, and skeletal developmental abnormalities, such as craniosynostosis. Caution against overtreatment with antithyroid medication is warranted, as these medications may cross the placenta in sufficient quantities to induce fetal goiter.  Guidelines for TSHRAb testing during pregnancy in women with previously treated  Fetal goiters and the associated fetal hypo-or hyperthyroid status were diagnosed accurately in mothers with Graves disease using a combination of fetal ultrasonography of the thyroid with Doppler, fetal heart rate monitoring, bone maturation, and maternal TSHRAb and antithyroid drug status 

Postpartum Thyroid Dysfunction

Postpartum thyroid dysfunction is much more common than recognized; it is often difficult to diagnose because its symptoms appear 1 to 8 months postpartum and are often confused with postpartum depression and difficulties adjusting to the demands of the neonate and infant. Postpartum thyroiditis appears to be caused by the combination of a rebounding immune system in the postpartum state and the presence of thyroid autoantibodies. Histologically,

Table 31.15 Guidelines for TSHRAb Testing During Pregnancy with Previously Treated Graves Disease

In the woman with antecedent Graves disease in remission after ATD treatment, the risk for fetal-neonatal hyperthyroidism is negligible, and systematic measurement of TSHRAb is not necessary.

Thyroid function should be evaluated during pregnancy to detect an unlikely but possible recurrence. In that case, TSHRAb assay is mandatory.

In the woman with antecedent Graves disease previously treated with radioiodine or thyroidectomy and regardless of the current thyroid status (euthyroidism with or without  thyroxine substitution), TSHRAb should be measured early in pregnancy to evaluate the risk for fetal hyperthyroidism.

If the TSHRAb level is high, careful monitoring of the fetus is mandatory for the early detection of signs of thyroid overstimulation (tachycardia, impaired growth rate, oligohydramnios, goiter). Cardiac echography and measurement of circulatory velocity may be confirmatory. Ultrasonographic measurements of the fetal thyroid have been defined from 20 weeks gestational age but require a well-tranied operator, and thyroid visibility may be hindered because of fetal head position. Color Doppler ultrasonography is helpful in evaluating thyroid hypervascularization. Because of the potential risks of fetal-neonatal hyperthyroid cardiac insufficiency and the inability to measure the degree of hypethyroidism in the mother because of previous thyroid ablation, it may be appropriate to consider direct diagnosis in the fetus. Fetal blood sampling through cordocentesis is feasible as early as 25 to 27 weeks gestation with less than 1% adverse effects (fetal bleeding, bradycardia, infection, spontaneous abortion, in utero death) when performed by experienced clinicians. ATD administration to the mother may be considered to treat the fetal hyperthyroidism.

In the woman with concurrent hyperthyroid Graves disease, regardless of whether it has preceded the onset of pregnancy, ATD treatment should be monitored and adjusted to keep free T₄ in the high-normal range to prevent fetal hypothyroidism and minimize toxicity associated with higher doses of these medications.

TSHR-Ab should be measured at the beginning of the last trimester, especially if the required ATD dosage is high. If the TSHRAb assay is negative or the level low, fetal-neonatal hyperthyroidism is rare. If antibody levels are high (TBII ≥40 U/L or TSAb ≥300%), evaluation of the fetus for hyperthyroidism is required. In this condition, there is usually a fair correlation between maternal and fetal thyroid function such that monitoring the ATD dosage according to the mother’s thyroid status is appropriate for the fetus. In some cases in which a high dose of ATD >20 mg/d of methimazole or >300 mg/d of propylthiouracil [PTU] is necessary, there is a risk of goitrous hypothyroidism in the fetus, which might be indistinguishable from goitrous Graves disease. The correct diagnosis relies on the assay of fetal thyroid hormones and TSH, which allows for optimal treatment.

Antithyroid Antibodies and Disorders of Reproduction

Women who have antithyroid autoantibodies before and after conception appear to be at an increased risk for spontaneous abortion ). Nonorgan-specific antibody production and pregnancy loss are documented in cases of antiphospholipid abnormalities (429). The concurrent presence of organ-specific thyroid antibodies and nonorgan-specific autoantibody production is not uncommon (429-431). In cases of recurrent pregnancy loss, thyroid autoantibodies may serve as peripheral markers of abnormal T-cell function and further implicate an immune component as the cause of reproductive failure. The clinical implications of these findings in management of patients with recurrent pregnancy loss are not known. 

Hypothalamic— pituitary (HP) causes of amenorrhea and ovulatory dysfunction

Primary HP amenorrhea is rare. If Kallmann syndrome (congenital HP amenorrhea associated with anosmia or hypo-osmia) is suspected, genetic counseling should be carried out before attempting pregnancy. Secondary HP amenorrhea due to stress, exercise and eating or weight disorders is mediated through the hypothalamic centers for gonadotropin-releasing hormone (GnRH). Treatment should be aimed at correction the underlying condition. Secondary amenorrhea due to pituitary infarction or blood-loss shock (Sheehan’s syndrome) is associated with adrenocorticotropic hormone (ACTH) and thyroid-stimulating hormone (TSH) deficiency, which should be corrected before attempting pregnancy. Obesity is a common cause of anovulation in developed countries. It has been estimated that 50% of women who are more than 20% over their ideal weight will be anovulatory or have luteal insufficiency. Often a 20% reduction in body weight is all that is required to restore fertility. Because obesity is associated with PCO, PCOS and insulin resistance, these disorders must be ruled out or treated first before attempting OI.

Table3.3. Ovulation dysfunction

Cause	Test	Finding	Treatment
Hypothalamic	FSH/LH	<5 mlU/mL	Diet/gonadotropin
Hyperprolactinemia	Prolactin	> 20 ng/mL	Bromocrptine
Polycystic ovaries	LH:FSH	2:1 ratio	Clomiphene
Adrenal hyperplasia	DHEAS	>180 μg/dL	Dexamethasone
Insulin resistance	Insulin	>20 μU/mL	Diet/metformin
Hypothyroid	TSH	>25 μU/mL	Levothyroxine
Menopause	FSH	>20 mIU/mL	Estrogen
Premenopausal	FSH	>10 mIU/mL	Clomiphene
Luteal insufficiency	Progesterone	<18 ng/mL	Clomiphene
Stress, starvation, anorexia, incarceration, excessive exercise, hypothalamic lesion (rare). FSH, follicle-stimulating hormone; LH, luteinizing hormone, DHEAS, dehydroepiandrosterone sulfate; TSH, thyroid-stimulating hormone.

Treatment with CC is effective only in patients with sufficient serum estradiol levels. After correction of underlying problems, including those related to stress, exercise and eating disorders, treatment with gonadotropins is effective in patients with low FSH levels, but it must be started at a low dose because of the possibility that ovaries unaccustomed to FSH will be hyperstimulated (see Chapter 8).

Hyperprolactinemia

Prolactin-secreting pituitary adenomas may cause primary amenorrhea or secondary amenorrhea, but are fortunately rare. Approximately 30% of women with secondary amenorrhea will have elevated prolactin levels, which may or may not be accompanied by galactorrhea and may be due to drug-induced lactotroph cell hyperplasia, rather than an adenoma. Prolactin levels of 20-100 ng/mL usually cause anovulation rather than amenorrhea, and may be secondary to hypothyroidism. Rarely, growth-hormone-secreting pituitary tumors will present as amenorrhea. Between 4% and 16% of women with elevated prolactin will be found on MRI to have an empty sella turcica, a benign condition. Pituitary adenomas are classified as macro (> 10 mm), and micro (< 10 mm). Dopamine agonist drugs are highly effective in treatment of both macro-and micro-adenomas. Once pregnancy occurs, dopamine agonists may be continued or stopped. In either case patients should be monitored with repeated prolactin levels and visual fields examinations (not MRI) or x-ray), lest an enlarging pituitary macro-adenoma damages the optic nerves. Patients may require CC in addition to dopamine agonist drugs to induce ovulation.

Polycystic ovaries (PCO), polycystic ovary syndrome (PCOS)

Polycystic ovaries (8-10 follicles < 8 mm per ovary) are the most common recognizable cause of ovulation dysfunction. PCO may be found in 10-25% of women with normal ovulation, and this causes a problem for infertility treatment, primarily because of the increased risk of multiple pregnancies during OI. Ovulation occurs, but is often late. The exact cause of delayed ovulation is unknown, but it may be because multiple follicles are competing for the same FSH pool. When polycystic ovaries are accompanied by excess androgens the condition is labeled PCOS. PCOS was originally described by Stein and Leventhal in 1935 as a variant of PCO, which previously had been believed to be associated only with excess estrogen  Wedge resection, removing 50-75% of each ovary, was introduced by Stein and Leventhal and remained the standard treatment for PCOS amenorrhea until the introduction of CC in the 1960s and, later, laparoscopic ovarian drilling. PCOS is caused by a defect in the rate of conversion of androgen precursors to estrogens (aromatization), as demonstrated by in-vitro culture of ovarian tissue from PCOS patients with radiolabeled progesterone and androgen precursors  The concentration of serum LH is increased, and the ratio of LH to FSH, which is normally 1:1, is 2:1 or greater. Treatment with CC is highly effective for PCO and PCOS.

Insulin resistance, metabolic syndrome

Insulin resistance (IR) is the cause of up to 25% of PCOS. It is differentiated from “classic” PCOS by elevated insulin levels, a normal LH-to-FSH ratio and failure to respond to clomiphene until insulin levels return to normal. Hyperinsulinemia, if left untreated, leads to hypertension, an increased risk of cardiovascular disease and gestational diabetes. Insulin resistance is considered to be one component of a condition formerly called syndrome X and now labeled metabolic syndrome. In addition to insulin resistance and obesity, the metabolic syndrome requires there to be three or more of the following [8]:

Hypertension 130/85 mm Hg or higher

Triglyceride levels 150mg/dL or higher

HDL cholesterol levels less than 50mg/dL

Abdominal obesity: waist circumference greater than 35 inches (89 cm)

Fasting glucose 110mg/dL or higher.

Laboratory findings in IR are: fasting insulin levels greater than 20 μU/mL and a fasting glucose-to-insulin ratio less than 4.5[9]. Due to wide variability among different ethnic groups, the 2-hour glucose/insulin response to a 75 g glucose load is considered more reliable. A 2-hour insulin level of 100-150 μU/mL indicates probable IR; 150-300 μU/mL is diagnostic of IR; and above 300 μU/mL indicates severe IR.  2-hour glucose of 140-199mg/dL indicates impaired glucose tolerance. 2-hour glucose above 200 mg/dL indicates non-insulin-dependent diabetes (type II diabetes). Patients with IR should not be labeled as type II diabetes unless, in addition to elevated insulin, the 2-hour glucose is also elevated. The first line of treatment for women with borderline and mild IR should be weight loss. Metformin 500-1,000 mg twice a day with meals is indicated for anovulatory women who continue to have elevated insulin levels after weight loss. Addition of CC is often necessary for ovulation [10].

Adrenal hyperplasia

Congenital adrenal hyperplasia is an inherited autosomal recessive enzyme defect that results in metabolic disorders and masculinization of newborn females. It is fortunately rare. A milder form, with onset at or following menarche, is variously labeled late-onset, adult-onset, acquired, partial, attenuated and non-classical adrenal hyperplasia. The most common form is due to 21-hydroxylase deficiency; other forms are due to 11β-hydroxylase deficiency and 3β-hydroxysteroid dehydrogenase deficiency. Clinical signs include mild hirsutism, increased skin sebum   causing mild acne, increased scalp sebum making daily hair washing necessary and mild hypertension. The diagnosis is confirmed by 17-hydroxyprogesterone (17OHP) levels ≥ 200 ng/dL or dehydroepiandrosterone sulfate (DHEAS) levels ≥ 180 μg/dL, which may also originate in the ovary. Elevated DHEAS is more common in mild cases and can be measured first. 17OHP should be measured first if there is virilization (hirsutism, male-pattern baldness or clitoral enlargement). Treatment for either defect is low-dose corticosteroid (0.5 mg dexamethasone or 5 mg prednisone) daily at bedtime. The addition of CC is often necessary or ovulation. Corticosteroids should be discontinued after ovulation, because of the risk of birth defects. Amenorrhea and excess androgen may be due to Cushing’s syndrome or acromegaly. Rapid development of virilization may be due to an androgen-producing tumor.

Thyroid causes of ovulation dysfunction

Hypothyroidism and hyperthyroidism are associated with menstrual dysfunction, with hypothyroidism being more common. TSH levels < 0.4 μU/mL are abnormal and indicate the need for additional studies to diagnose hyperthyroidism. Although TSH levels ≥ 4.5 μU/mL are generally accepted as diagnostic of subclinical hypothyroidism, some medical and reproductive endocrinologists consider TSH levels ≥ 2.5 μU/mL as abnormal and contributing or ovulatory dysfunction. Hypothyroidism during pregnancy is linked to miscarriage and mental retardation in children. Patients with TSH levels ≥ 4.5 should be treated with levothyroxine (LTX) 50-75 μU per day before attempting pregnancy. Treatment with LTX 25-50 μU per day may be considered for anovulatory patients when TSH levels are between 2.5 and 4.5 μU/mL while pregnant, patients with TSH levels ≥ 2.0 μU/mL should be retested monthly during the first trimester and again postpartum. Newly pregnant patients already using LTX should have the dose increased by 20-50% (at least 25 μg) as soon as pregnancy is confirmed. TSH levels are approximately 30% lower when measured while patients are fasting, and should not be obtained at the same time as tests (insulin, glucose, and growth hormone) that require fasting.

Premenopause, menopause

The diagnosis of menopause is customarily made when a woman is amenorrheic for six months or more and serum FSH is ≥ 20 mIU/mL Care should be taken not to label a patient as menopausal and therefore infertile on the basis of a single FSH value ≥ 20. FSH levels vary widely during the perimenopausal years: the first author has seen FSH levels as high as 26 mIU/mL followed by ovulation and conception during the same cycle. As a general rule, patients with FSH levels ≥ 12 will respond poorly to gonadotropin stimulation and will not become pregnant. CC has been found to be as effective as or more effective than gonadotropins for OI in IUI patients aged 38 and older . When cycle day 3-5 FSH levels are in the range of 8-12 mIU/mL, the CC challenge test (CCT) described in this chapter [12] will help to differentiate patients who can become pregnant on their own or can benefit from fertility treatment from those unlikely to become pregnant.

Luteal insufficiency and luteinized unruptured follicle syndrome

One of the most common ovulatory disorders in patients over the age of 28 is luteal insufficiency (LI). Patients with LI ovulate but pregnancy fails to occur or ends in early miscarriage. At one time the diagnosis was made by endometrial biopsy, a procedure that was uncomfortable and risked injury to an implanted embryo. Today the diagnosis is more often based of serum progesterone levels and the appearance of the endometrium on ultrasound (US). Although some textbooks and laboratory manuals report serum progesterone concentrations of 5-10 ng/mL as evidence of normal ovulation, many infertility experts believe that levels lower than 16-18 ng/mL are associated with failure to implant or early miscarriage. On ultrasound, the mid-luteal phase endometrium should have a thickness ≥ 9 mm and the endometrial pattern should be homogeneous and hyperechogenic . A low progesterone concentration and inadequate endometrial development, despite ovulation, is most often due to inadequate follicular development in the proliferative phase of the cycle. In the luteinized unruptured follicle syndrome (LUF), ovulation does not occur despite an LH surge, an increase in progesterone concentration, physiological changes normally associated with ovulation (shift in basal body temperature, cervical-mucus thickening) and a change in the endometrial pattern. However, there is no change in size of the dominant follicle on ultrasound, and no operculum (stigma of ovulation) is found at laparoscopy. The underlying defect may be either inadequate follicular development or a weak LH surge. Treatment of LI with CC is preferred to progesterone supplementation with oral, vaginal or intramuscular progesterone because it corrects the underlying defect of inadequate follicular development. CC is also an effective treatment for LUF, but some patients may require human chorionic gonadotropin (HCG). Treatment with dexamethasone has been tried with less success.

Clinical management

Cycle day 3-5 of regular or induced menses: Ultrasound is performed to evaluate the endometrium, to determine the number of antral follicles and to rule out ovarian (clear cysts larger than 1 cm, solid or complex cysts of any size).

Endometrial thickness should be < 6mm. an overly thick endometrium found on cycle day 3-5 will ordinarily shrink to < 6 mm in 2-4 days. Failure to do so is an indication for further evaluation.

Antral follicle counts greater than 8-10 per ovary signify increased probability of triplet or higher-order pregnancy and the need to start with a low dose of CC or TMX and repeat US before ovulation.

If a corpus luteum cyst larger than 1 cm is present, serum progesterone should be measured. Initiating OI when progesterone is > o.9 ng/mL will result in fewer preovulatory follicles. (For management see advanced protocol.)

If no significant cysts are present, and endometrium is < 6 mm, a single 50 mg tablet of CC or 20 mg tablet of TMX is taken daily for five days.

Couples are advised to have sexual relations every other day beginning on the tenth cycle day.

If menses occur within the usual time frame cycle day 26-32-ovulation is assumed to have occurred and the same dose is repeated for two additional cycles.

If ovulation does not occur and there are no side effects, the dose is increased by one tablet each succeeding cycle to a maximum of three tablets (150 mg CC, 60 mg TMX). All tablets are taken at the same time each day.

Side effects of CC are hot flashes (11% of patients) and visual symptoms (2% of patients) [16]. Visual symptoms may be blurring or spots and flashes (scintillating scotoma). CC and TMX should be discontinued immediately if visual symptoms occur, but can be restarted at a lower dose in the next cycle.

Use of preovulation US to avoid multiple pregnancy and to time timed intercourse (TI) or IUI

US is performed 5-7 days after the last tablet of CC or TMX.

If no more than two follicles are ≥ 12 mm and the lead follicle is at least 18 mm, 5,000-10,000 IU of human chorionic gonadotropin (hCG) or 250 μg recombinant hCG (rhCG) may be given for IUI or timed intercourse (TI) 30-36 hours later.

If more than two follicles are ≥ 12 mm and age is < 38 years, the cycle is cancelled to avoid triplet or higher order pregnancy. The couple is warned not to have unprotected sexual relations for five days.

Use of LH testing for TI and IUI

Patients are instructed to begin LH monitoring on the 10th cycle day using a home LH test kit. When the LH test indicated that ovulation is imminent by a change in color, usually on the 12th or 13th day, the IUI patient notifies the clinic or office and arrangements are made to perform IUI within 24 hours. Alternatively, TI couples should have sexual relations within 24 hours.

Notes regarding the basic protocol

Whether to start the third or fifth day is based on the length of the patient’s untreated cycle, with the aim of maintaining a minimum of six days between the last pill and ovulation, in order to negate the antiestrogen effect of CC. thus patients with 28-day cycles are started on the third day and patients with 30-day or longer cycles are started on the fifth day.

Because TMX does not have an antiestrogen effect on cervical mucus or endometrium, it is not necessary to start as early as CC. TMX can be started as late as the seventh day.

In patients who are amenorrheic or have a prolonged time between cycles, it may be necessary to induce menses before starting OI. Inducing menses with oral contraceptive (OC) pills or medroxyprogesterone acetate (MPA) is no longer acceptable due to the possibility of fetal masculinization or birth defect if a patient is pregnant. Unmodified progesterone is effective in inducing menses if the endometrial thickness is 6 mm or greater, and will support rather than harm an early pregnancy.

Progesterone can be administered as a single injection of 50-100 mg in oil, as a vaginal gel or as tablets 90-100 mg 1-3 times daily for 7-14 days, or as 200 mg micronized oral tablets 3-4 times  daily for 7-14 days. Menses should occur within 14 days of injection or two days following the last vaginal or oral progesterone.

The preovulation LH surge normally occurs by the 16th cycle day, or nine days after the last oral pill. If the patient does not detect a change within the expected time, the OI drug may have failed to induce follicular development, follicular development may be delayed but be otherwise satisfactory, or the patient may have failed to detect the LH change. Which of these has happened can be determined by performing a pelvic US and measuring serum LH, estradiol and progesterone. In some cases IUI is still possible, while in others the information will be used to plan treatment in the next cycle.

When IUI is planned, the basic protocol calls for insemination twice, six and eight days after the last pill. When IUI is timed by LH monitoring or hCG administration, only a single IUI is needed.

Unless it is a planned IUI cycle, a postcoital test should be performed during the first CC cycle and should be repeated in subsequent cycles if the CC dose is increased. IUI can be advised if the PCT test is abnormal.

The effectiveness and safety of OI with oral drugs are increased if the starting day is determined by menstrual day 3 estradiol and progesterone levels, if the initial dose is determined by body weight and midluteal progesterone level, and if preovulation follicular and endometrial response are monitored by ultrasound.

 Additionally, the day and time of IUI or timed intercourse can be regulated to fit patient and clinic schedules by triggering ovulation with hCG when the preovulatory ultrasound and estradiol level indicate that follicle development is sufficiently advanced.

Use of estradiol and progesterone levels to choose the starting day

CC and TMX require serum estradiol levels ≥ 50 pg/mL to be effective. Ipsilateral follicle development is inhibited when the serum progesterone level is ≥ 0.9 ng/mL Initiating OI with CC or TMX before these levels are attained will result in no or reduced follicle development. Serum levels usually reach these parameters on the third menstrual cycle day, but may require seven days or longer in patients with PCOS or persistent corpus luteum cysts. Serum estradiol levels normally double every two days, and progesterone levels normally decrease 50% per day during the early follicular phase of the cycle, and do not need to be rechecked unless they would require more than three days to reach the level required to start. Delaying the start of CC or TMX until hormone levels are in the desired range will increase the chance of successful stimulation.

Use of body weight to select the initial dose of CC or TMX

The dose of CC and by inference TMS, necessary to induce ovulation is proportional to body weight A starting dose of 100 mg CC or 60 mg TMX is recommended for patients who weigh > 165 I (75kg). A starting dose of 25 mg CC or 10-20 mg TMX is recommended for women who weigh < 100 I (45kg).other weights should be started on 50 mg CC or 20-40 mg TMX.

Use of mid-luteal progesterone to select the dose of CC or TMX

Progesterone levels in the mid-luteal phase of CC cycles that result in term pregnancies average 37 ng/mL, compared to 22 ng/mL in spontaneous cycles . Progesterone levels in the mid-luteal phase, 5-7 days after ovulation, that are less than 18 ng/mL are evidence of possible luteal insufficiency. Levels less than 15 ng/mL are rarely associated with ongoing pregnancy. When progesterone levels are less than 18 ng/mL following CC, oral or vaginal supplementation (see notes regarding basic protocol) should be considered in the current cycle, and the dose of CC or TMX should be increased in 50 mg and 20 mg increments respectively in subsequent cycles until progesterone levels are ≥ 18 ng/mL

Effect of increasing the dose of CC or additional days of treatment

Increasing the dose of CC from 50 mg in the first cycle to 100 mg in the next cycle results in minimal increases in average number of small, medium and large follicles (≥ 12 mm from 2.4 to 2.6, ≥ 15 mm from 1.7 to 1.9, ≥ 18 mm from 1.2 to 1.3)  Extending the number of days that 50 mg of CC is taken to 8 or 10 days has been shown to result in ovulation in patients who did not respond to 200 or 250 mg CC for five days in a small serried [20]. The benefit of increasing the dose of CC or number of days CC is taken must be balanced against the possibility of increased antiestrogen effect on the endometrium and cervical mucus. The effects of increasing the dose of TMX or extending the length of TMX treatment have not been reported, but they would not be expected to have an adverse effect on endometrium or cervical mucus. When additional numbers of follicles are desired, increasing the dose of CC or TMX will have little effect compared to adding or substituting gonadotropins 

Use of preovulation ultrasound (US) to predict ovulation and multiple pregnancy

Preovulatory US performed 5-7 days after the last CC or TMX allows the ovulation day to be predicated for timed IUI or intercourse, and the number of preovulatory follicles to be assessed in order to cancel cycles if an excessive number of preovulatory follicles are present.

      In CC and TMX cycles the lead follicle is usually 18-20 mm in diameter on the day of spontaneous LH surge and 20-24 mm on the day of ovulation. The dominant follicle and others destined to ovulate ordinarily increase at a rate of 2 mm per day from cycle day 10 until ovulation. The size of the leading follicle on cycle day 12-14 can be used to predict when a spontaneous LH surge and ovulation will occur. If predicted to occur at an inconvenient time for performing IUI, ovulation can be induced by HCG (5,000 or 10,000 IU) or rhCG 250 mg if the lead follicle is at least 16 mm and estradiol concentration is consistent with the number of follicles. The serum estradiol level should be 180-250 pg/mL per mature follicle.

      The possibility of multiple pregnancies can be estimated from the number of follicles expected to be ≥ 10-12 mm on the day of spontaneous LH surge or HCG injection. This allows sufficient time to proscribe intercourse or cancel IUI if there is risk of triplet and higher-order multiple pregnancies  or a desire to avoid a twin pregnancy. The probability of any pregnancy in CC cycles is most closely related to the number of follicles ≥ 15 mm, rather than or smaller or larger sizes. Multiple pregnancy rates in CC and TMX cycles are most closely related to the number of follicles ≥ 12 mm on the day of spontaneous LH surge or HCG injection, but follicles as small as 10 mm on the day of HCG can result in pregnancy . Pregnancy rates do not increase appreciably when there are more than four follicles ≥ 15 mm in CC cycles .

Use of preovulatory ultrasound (US) to evaluate endometrial receptivity

Preovulatory US enable evaluation of endometrial receptivity by measurement of endometrial thickness and observation of the endometrial pattern. Ideally, endometrial thickness will be ≥ 9 mm, and endometrial pattern will be triple line on the day of LH surge or HCG injection . If the endometrial thickness is < 9 mm on preovulation ultrasound, administration of HCG should be delayed. If the LH surge has already started, vaginal estrogen (2 mg micronized estradiol tablets or the equivalent twice daily), or oral estrogen (2 mg micronized estradiol tablets or the equivalent four times daily), can be used provided that hCG is given to induce ovulation, lest the estrogen suppresses the LH surge, whether adding estrogen increases endometrial thickness is unproven. Thickness normally increases at a rapid rate in the late proliferative phase of CC cycles as the endometrium escapes the antiestrogen effect of CC, and eventually equals or surpasses thickness in spontaneous cycles . In subsequent cycles endometrial thickness may be improved by using a lower dose of CC, by switching to TMX, or by taking oral or vaginal estrogen (2 mg daily) concurrently with and following CC.

Use of serum LH monitoring to predict ovulation day

If a baseline LH has been measured at the start of the cycle, a repeat LH measurement on cycle day 12-14 will provide an indication of how soon spontaneous ovulation will occur. Ovulation normally occurs within 24 hours from the time that LH levels are twice the baseline level. A smaller increase above baseline level indicates the beginning of the LH surge and ovulation in 36 hours. A sharp dip in serum LH is often seen one day before the start of LH surge and ovulation in 36 hours. A sharp dip in serum LH is often seen one day before the start of LH surge. In PCOS patients, LH levels are often ≥ 20 mIU/mL during the early follicular phase but decrease to < 10 mIU/mL one or two days before ovulation and rise again at the beginning of the LH surge. Repeated LH determinations combined with US and estradiol levels may be needed to determine when the LH surge starts in PCOS patient.

Use of human chorionic gonadotropin (HCG) or recombinant  HCG (rhCG)

Use of HCG or rhCG in CC and TMX cycles is seldom necessary to induce ovulation. It is used in cc and TMX cycles to induce. It is use in CC and TMS cycles to induce ovulation at a time convenient for IUI or TI. Use of HCG or rhCG does not increase the incidence of multiple pregnancies.

Adjunctive treatment

Pretreatment with oral contraceptive

Pretreatment with combination oral contraceptives (OC) the cycle before taking CC significantly increased ovulation rates and pregnancy rates in a systematic review of randomized controlled studies . Multiple pregnancy rates were also increased. Combination OCs containing 30-35 μg estradiol are more effective than combination OCs containing 20 μg estradiol or multiphase OCs for most patients, but may reduce follicle development in a few patients. Pretreatment with OCs is particularly beneficial in PCOS patients, because they suppress serum and ovarian androgen levels.

Addition of dexamethasone

Adding dexamethasone to CC cycles in patients with or without increased DHEAS concentrations significantly improves ovulation and pregnancy rates compared to CC, according to a systematic review of randomized controlled studies; however, it also increased multiple pregnancy rates In addition to suppressing adrenal androgen, dexamethasone partially negates the antiestrogen effect of CC on endometrium  Dexamethasone is administered as a single 0.5 mg tablet at bedtime from cycle day 1 until six days after ovulation. At the Fertility Institute of New Orleans dexamethasone is not used routinely in OI cycles, but is added if serum DHEAS levels are ≥ 180 μg/dL .

Additional metformin

Metformin improved ovulation in women with insulin resistance and hyperandrogenism associated with PCOS who were resistant to CC, according to a systematic review of multiple small prospective randomized studies . However, in a large randomized prospective study of anovulatory infertile women, not previously found to be CC-resistant, metformin alone at a maximum dose of 1,000 mg per day was not effective in inducing ovulation (7% live births) compared to CC (23% live births), or the combination of metformin and CC (27% live births) .Despite conflicting results, the combination of metformin and CC should be tried in patients who are resistant to CC, before switching to gonadotropins, because of its low incidence of multiple pregnancies. The usual dose is 1,000-1,500 mg per day, administered in a single or divided dose with meals.

Treatment results

Pregnancy rates in CC and CC-IUI cycles vary widely, depending on semen source and quality, number of follicles developed during stimulation, reason for treatment, age and how many previous treatment cycles have been performed. In our experience at the Fertility Institute of New Orleans, average pregnancy rates per cycle during four cycles of CC-IUI range from a low 3.2% per cycle for sub-IUI-threshold sperm to 20.4% per cycle for luteal insufficiency, and are 16.5% per cycle when donor sperm is used for IUI ,Compared to hMG-IUI cycles, pregnancy rates per CC-IUI cycle are 50% lower for ages < 32 and 33% lower for ages 32-38, but equal or higher for ages 38-44 (Fig.7.4) [21]. The difference in pregnancy rates before age 38 was entirely due to the number of preovulatory follicles in CC-IUI cycles compared to the number of preovulatory follicles in hMG-IUI. On average, 21% of CC cycles were monofollicular, 32% had two follicles and 47% had three or more follicles ≥ 12 mm. by comparison, 8% of gonadotropin cycles were monofollicular, 12% had two follicles and 80% had three or more follicles ≥ 12 mm.