Serum anti-Müllerian hormone levels remain high until late reproductive age and decrease during metformin therapy in women with polycystic ovary syndrome.

BACKGROUND Anti-Müllerian hormone (AMH) is secreted by granulosa cells of ovarian early developing follicles and its serum levels have been shown to correlate with small antral follicle number. Since the pronounced androgen secretion from follicles/stroma in women with polycystic ovary syndrome (PCOS) remains until late reproductive age, and since AMH reflects the number of antral follicles, it was of interest to study the possible age-related relationship between AMH, androgens and follicle number in women with PCOS and in control women. Moreover, the possible effect of metformin on serum AMH levels and the relationship to follicle count and volume were studied. METHODS Forty-four healthy women (aged 21-44 years) and 65 women with previously diagnosed PCOS (aged 16-44 years) participated in the study. Serum basal AMH levels were correlated with those of serum androstenedione, testosterone, estradiol (E2), LH, FSH and inhibin B, and with follicle number. The effect of metformin on serum AMH concentrations, follicle number and ovarian volume was studied in 26 women (aged 20-41 years) with PCOS after 6 months of treatment. RESULTS Serum AMH levels were 2- to 3- fold higher in PCOS women than in healthy women. In control women, serum AMH levels correlated positively with those of serum androstenedione (r = 0.564, P < 0.001) and testosterone (r = 0.328, P = 0.036) and negatively with serum FSH concentrations (r = -0.374, P = 0.012) and age (r = -0.691, P<0.001). In women with PCOS, serum AMH levels correlated positively with those of androstenedione (r = 0.311, P = 0.011) and testosterone (r = 0.310, P = 0.011) and with follicle count (r = 0.352, P = 0.012), and negatively with age (r = -0.300, P = 0.014). Serum AMH levels, the number of antral follicles and ovarian volume decreased significantly during metfromin treatment. CONCLUSIONS Serum AMH levels decreased with age both in healthy women and in women with PCOS, although they were always 2- to 3-fold higher and remained elevated until 40 years of age in PCOS subjects. Thus, since serum AMH levels correlate well with antral follicle count and serum androgen levels, the measurement of AMH could be used as a tool to assess ovarian ageing, to diagnose polycystic ovaries/PCOS and to evaluate treatment efficacy.