Endocrine Abstracts

Background: Anti-Müllerian hormone (AMH) has a positive linear relationship to antral follicle count (AFC) in healthy women. However, studies of intra-follicular AMH-levels indicate a non-linear relation to AFC. It is speculated whether high AMH in polycystic ovary syndrome (PCOS) women is due to overactive follicles rather than directly reflect AFC.

Study design: We used data from a previous case–control study, including 262 women with prior term (controls) and preterm births (cases) in 1999–2006. Fasting blood tests, clinical and vaginal ultrasound examination were performed. The participants were categorised to have PCOS, polycystic ovary morphology (PCOM) or to be normal controls.

Methods: PCOS was defined according to the Rotterdam criteria, PCOM was defined as having ≥12 pre-antral follicles measuring 2–9 mm in diameter, and/or increased ovarian volume (>10 ml) in at least one ovary. We analyzed AMH/AFC ratio, adjusted for age, BMI, androstenedione, free testosterone index, and insulin.

Main results: AMH had a similar linear relationship to AFC in women with PCOS, PCOM, and normal controls. Other variables included in the multivariate analysis did not change this association. The AMH/AFC ratio was similar in the three groups.

Limitations: The results apply for women who have given birth. We did not have the possibility to correct for a distribution towards either small follicles (>2 mm) or larger follicles (<9 mm).

Implications of the findings: AMH seems to be a reliable predictor of AFC independent of PCOS diagnosis or ovarian morphology. AMH can be used as a substitute indicator of AFC in most women of fertile age.