Q.
1: What are the common and uncommon tests for ovarian reserve ?
Ans: The estimation of ovarian reserve can be done by subjecting the patient to
various ovarian reserve tests (ORTs). These tests are hormonal tests and
ultrasound.
For a long era, hormonal tests were
commonly used for assessment of ovarian reserve.
These tests are as follows:
A)
Static
tests:
1)
day 2/3 FSH(follicle stimulating hormone)
2)
Day 2/3 E2 (estradiol)
3)
Day 3 FSH and LFl(leutinizing hormone)
4)
Inhibin B (assays are variable, requires
validation and there is cycle to cycle variability
5)
AMF (Antimullerian hormone)
B)
Dynamic
tests:
6)
Clomiphene citrate challenge test (CCCT)
7)
GnRh Analogue stimulation test (CAST)
8)
Exogenous FSH ORT ( EFFORT).
Of al these
eight tets mentioned above only
1,2, 3 & 5 are popular and
used in day to day clinical practice . Other tests have not become popular in
clinical practice due to their complexity and low reliability but still occasionally
used for research settings. Initially , Ovarian reserve was conventionally
assessed by basal(day 2-3) serum follicle stimulating hormone(S.FSH). FSH is
controlled by negative feedback of oestradiol. Normal FSH with low E2 indicates
normal hypothalamo-pituitary - gonadal axis. The level of FSH increases with
increasing age and indicates low ovarian reserve. But the reliability of FSH is
challengeable because of its pulsatile and circadian release and its isoforms.
Moreover there is no cut off for nonpregnanr women and possibility of natural
fertility. Currently ART specialist are paying more stress on AMH & AFC and
partly on ovarian volume.
What is our prsent knowledge on AMH and ovarian response to superovulation
in ART cycle where gonadotrophins are used??
Q. 2: Given choice which tets you will prefer
to assess ovarian reserve? Ans : AMH( Antimullerian hormone) has been found to be a very reliable and more
accurate than S.FSH , for assessment of ovarian reserve. Chemically it (Anti-Mullerian
hormone (AMH) is a dimeric glycoprotein.
Q. 3: Which cells specifically synthesize
AMH and at what stage it is secreted more preferentially?? Ans: AMH is exclusively produced by granulosa
cells of A) preantral (primary and secondary) and B) small antral follicles
(AFs) in the ovary.
At what cycle age
of follicular growth AMH can be estimated?? Ans: The
production of AMH starts following follicular transition from the primordial to
the primary stage, and it continues until the follicles reach the antral
stages, with diameters of 2-6 mm. The highest level of AMH expression is
present in granulosa cells of secondary
antral, preantral, and small antral follicles up to 6 mm in diameter. Therefore
level of AMH may represent the population of these follicles.
Q. 4. How
does AMH level correlates with AFC? Ans. AMH levels strongly correlate with
basal antral follicle count (AFC) measured by transvaginal ultrasonography. AMH
however can be used to predict both poor response and hyperresponse.
Q. 5. . What is the exact function of
AMH?? Ans; The function of AMH is to modulate primordial follicle
recruitment. It inhibits the action of FSH on the follicular growth
and selection. AMH is considered to be reflective of FSH independent
follicular growth. It is therefore a direct measurement of ovarian reserve. AMH
reflects quantitative and qualitative assessment of ovarian reserve.
Unlike other biochemical markers, it can be measured
on any day of the cycle and does not exhibit intercycle variability. AMH level
is constant, not related to gonadotrophin secretion and independent of the day
of cycle.
Various threshold values, 0.2—1.26 ng/ml, have been
used to identify poor responders with 80-87% sensitivity and 64—93% specificity.
It is considered that at levels 0.5—1.26 ng/ml, AMH
indicates perimenopausal transition within 3—5 years.
The use of nomograms identifies the age-related
physiological decline in the AMH levels and thus ovarian reserve, and abnormal
deviations can be used for counseling couples wishing to delay childbirth.
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