LAUSR

Abstract This observational study compares the ratio of serum anti-Mullerian hormone (AMH) to the total antral follicle count (AFC) (as a marker of AMH production per follicle) in the various phenotypes of women with polycystic ovary syndrome (PCOS) and isolated polycystic ovarian morphology (PCOM). Two hundred and sixty-two women were recruited. Women with PCOS were divided into four phenotypes based on the diagnostic inclusion criteria of oligo-anovulation (OA), hyperandrogenism (HA) and polycystic ovarian morphology (PCOM). These included Group A (OA + HA + PCOM), Group B (OA + HA), Group C (HA + PCOM) and Group D (OA + PCOM). A ratio of serum AMH to total AFC was calculated and expressed as the AMH/AFC ratio which was compared in the phenotypes of PCOS and isolated PCOM. The median AMH/AFC ratios in PCOS-A, PCOS-D, PCOS-C and PCOM were 1.5, 1.6, 1.2 and 1.1, respectively. There were significant differences in the groups compared [F(3, 238) = 6.14, p = 0.000)]. The ratios were significantly higher in the oligo-anovulatory phenotypes PCOS-A and PCOS-D than the PCOM (p = 0.004 and 0.002, respectively). There was no significant difference in the ratio between ovulatory phenotype PCOS-C and PCOM (p = 0.59). The role of androgens and LH in per-follicle AMH production remains limited. The findings support the hypothesis of a key role for AMH in the mechanism of anovulation in PCOS.