Funicular MONIRORIG IN SUB FERTILITY PRACTICE ovulation INDUCTION

Pelvic Ultrasound: Basal Scan-& Findings at Basal endocrine evaluations & treatment thereof Pelvic Ultrasound.

When first scanning the pelvis, many radiographers and radiologists suggest per­forming a transabdominal scan to first obtain an overview of the pelvic organs, and second to assess the kidneys and renal tract if indicated. Subsequently, a transvaginal ultrasound examination of the pelvic organs is preferred to the transab­dominal approach as it not only obviates the need for a full bladder with its associated Discomfort but also allows high-frequency probes (5-7.5 MHz) to be used so that higher resolution and greater precision in measurements or measurements of the pelvic structures, follicular diameters and endometrial thickness be achieved. It is especially advantageous in patients who are undergoing assisted conception as they commonly have lower abdom­inal scars that impair the penetration of ultrasound; furthermore, periadnexal adhe­sions may tether the ovaries deep in the pelvis and limit the elevation of these structures that normally occurs when the bladder is filled for a transabdominal scan. A study the follicles were more sharply defined in 90% of cases when the transvaginal approach was used compared with only 41% with a transabdominal approach [21]. The same study found that the numbers and sizes of the dominant follicles correlated better with the serum oestradiol concentrations when transvaginal scanning was used.

An ultrasound assessment of ovarian volume and AFC in the early follicular phase has been used as a predictor for ovarian response before IVF treatment, with small-volume ovaries indicating reduced ovarian reserve (see above).

Ovarian Morphology

We recognise in the ovary three distinct morphological appearances: normal polycystic and multicystic. Multicystic ovaries are characteristically observed in pubertal girls and women recovering from weight-loss-related amenorrhoea. These multicystic (or multifollicular) ovaries are normal in size or slightly enlarged and contain six or more cysts that are 4-10 mm in diameter  in contrast to women with polycystic ovaries (PCOs), the stroma is not increased. The multicystic ovary appears to develop as a consequence of reduced hypothalamic secretion of GnRH, resulting in subnormal stimulation of the ovaries by the gonadotropins. The multicystic ovary has a normal response to exogenous Stimulation, by either pulsatile GnRH or gonadotropins, and the ultrasound appearance of the ovary usually reverts to normal.

Polycystic ovaries are a separate entity and have a distinct response to induction of ovulation and ovarian stimulation for IVF. The association of enlarged, sclerocystic ovaries with amenorrhoea, infertility and hirsutism was first described by Stein and Leventhal in 1935, and it is now known as PCOS. Since then, it has become apparent that polycystic ovaries may be present in women who are non-hirsute and who have regular menstrual cycles. Thus, a clinical spectrum exists between the typical Stein—Leventhal picture (PCOS) and the symptomless (PCO). Even patients described as having the PCOS exhibit considerable heterogeneity.

Differentiating between PCO and PCOS

It is important to differentiate between PCO and the PCOS. PCO describes the
morhological appearance of the ovary whereas PCOS is only appropriate when PCOs
are round in association with a menstrual disturbance (amenorrhoea or, more commonly, oligomenorrhoea) and/or the complications of hyperandrogenism (acne and
hirsutism, PCOS also is associated with endocrinological abnormalities and, in particular, with elevated serum concentrations of androgens (T, androstenedione) and LH. As with the clinical picture, these changes are variable and patients with PCOS may have normal endocrine concentration. The diagnosis of PCO is therefore best made not on the clinical presentation but rather on the ovarian morphology.

. There have been many attempts to redefine the morphological appearance of the PCO by using transvaginal ultraso­nography, three-dimensional transvaginal ultrasonography and magnetic resonance imaging (MRI; Figure 5.14). Ovarian stromal volume has been correlated with serum T concentrations and may provide more useful informa­tion then the volume of the cysts. Furthermore, ovarian volume correlates well with stromal volume as a marker of hyperandrogenism and is easier to measure in practice than stromal volume. Ovarian volume is usually greater than 10 ml, compared with the normal ovarian volume of ml.

The latest international consensus definition for the ultrasound assessment of the PCO is as follows:-The polycystic ovary should have at least one of the following: either 12 or more follicles measuring 2-9 mm in diameter or increased ovarian volume (>10 cm³). If there is evidence of a dominant follicle (>10 mm) or a corpus luteum, the scan should be repeated the next cycle.

The subjective appearance of polycystic ovaries should not be substituted for this definition. The follicle distribution should be omitted as well as the increase in stromal echogenicity and/or volume. Although the latter is specific to PCO, it has been shown that the measurement of the ovarian volume is a good surrogate for the quantification of the stroma clinical practice.

Only one ovary fitting this definition or a single occurrence of one of the above-mentioned criteria is sufficient to define the PCO. If there is evidence of a dominant follicle (>10 mm) or corpus luteum, the scan should be repeated the next cycle. The presence of abnormal cysts or ovar­ian asymmetry, perhaps suggesting a homogeneous cyst, necessitates fur­ther investigation.

This definition does not apply to women taking the oral contraceptive pill, as ovarian size is reduced, even though the polycystic appearance may persist.

A woman having PCO in the absence of an ovulation disorder or hyperan­drogenism (asymptomatic PCO) should not be considered as having PCOS, until more is known about this situation.

In addition to its role in the definition of PCO, ultrasound is helpful to pre­dict fertility outcome in patients with PCOS (response to clomiphene citrate, risk for ovarian hyperstimulation syndrome (OHSS), decision for in vitro maturation of oocytes). It is recognised that the appearance of PCOs may be seen in women undergoing ovarian stimulation for IVF in the absence of overt signs of the PCO syndrome. Ultrasound also provides the opportunity to screen for endometrial hyperplasia following technical recommendations should be respected:

State-of-the-art equipment is required and should be operated by appropriately trained personnel.

Whenever possible, the transvaginal approach should be preferred, particularly in obese patients.

Regularly menstruating women should be scanned in the early follicular phase (days 3-5). Oligo-/amenorrhoeic women should be scanned either at random or between days 3 and 5 after a progestogen-induced bleed.

If there is evidence of a dominant follicle (>10 mm) or a corpus luteum the scan should be repeated the next cycle.

Calculation of ovarian volume is performed using the simplified formula for a prolate ellipsoid (0.5 x length x width x thickness).

Follicle number should be estimated both in longitudinal and anteroposterior cross-sections of the ovaries. Follicle size should be expressed as the mean of the diameters measured in the two sections.

Since this consensus was published in 2003, there have been further debates about the threshold number of follicles and appropriate size, with the suggestion that it is the smaller follicles (2-5 mm) that are more relevant and that a PCO should have at least 19 per ovary; furthermore, an concentration of >35 pmol/L might be a better and more consistent discriminator.

Prevalence

The prevalence of PCOs in women with ovulatory disorders has been well docu­mented. Using high-resolution ultrasound, it has been shown that as many as 87% of patients with oligomenorrhoea and 26% with amenorrhoea have PCOs [23]. We also have identified PCOs in women with hypogonadotropic hypogonadism who attended our ovulation induction clinic, and although these patients had no endogenous production of gonadotropins, they responded to stimulation in a characteristically polycystic manner with a sudden growth of multiple follicles. PCOs also have been found in 33% of normal young women. The prevalence in patients referred for IVF is not well known. We studied more than 500 patients who underwent IVF and found 34% to have ultrasound-detected PCO.

Ovarian Cysts

Besides making a careful assessment of ovarian morphology, it is necessary to perform a baseline ultrasound scan of the ovaries before commencing ovarian stimulation to detect the presence of ovarian cysts through. It is obviously necessary to record the presence of any cystic structures before commencing ovarian stimula­tion to accurately monitor the development of new follicles. There remains controversy as to the effect of ovarian cysts on the treatment cycle. Although it has been suggested

Hormonal agents and those cysts that might arise as a result of hormonal stimulation because of the exaggerated release of the gonadotropins that occurs when GnRH ago­nist therapy is commenced (e.g. pre-treatment with the combined oral contraceptive pill reduces the occurrence of such GnRH agonist-stimulated cysts).

The situation is slightly different in patients who are undergoing ovulation induction for anovulatory infertility. In such patients, cysts are usually functional and secrete oestrogens or progesterone. If a cyst is detected on a baseline ultrasound scan, the usual policy is to commence ovarian stimulation only after the patient has had a spontaneous menstrual bleed, indicating that the endogenous secretion of ovarian hormones has returned to baseline levels. Further confirmation of this baseline return is provided by a thin endometrium (<5 mm). Simple ovarian cysts that are less than 5 cm in diameter rarely require surgical intervention. If there is any doubt about the nature of a cyst, then tumor markers should be measured (e.g. CAl25) and surgi­cal removal considered to make a histological diagnosis before commencing ovarian stimulation.

If the patient is known to have endometriosis, it is important to avoid aspirating the cyst, either before ovarian stimulation is commenced or during the oocyte retrieval procedure itself because of the risk of infection (see Chapter 14). An endometrioma has the characteristic hazy, echodense appearance of blood in a cyst. Inadvertent, or unavoidable, aspiration of an endometrioma necessitates full antibiotic cover. Dermoid cysts (mature cystic teratoma) are sometimes seen in women of repro­ductive age and may be difficult to distinguish from endometriomas, as both may be

Bilateral with a hazy, homogeneously echodense appearance of lipid matter in Dermoids and blood in endometriomas. Dermoid cysts can sometimes be differentiated by brightly echogenic areas caused by the presence of solid components.