Endocrine Abstracts

Recent studies have shown that serum concentrations of AMH (produced by granulosa cells of the human ovary) are positively related to the number of antral follicles and are negatively correlated with age. Like inhibin B (also a granulosa cell product) AMH is thought to be a useful clinical marker of follicle reserve. Serum AMH concentrations have been reported to be higher than normal in women with polycystic ovary syndrome (PCOS), which is characterised by an excess of antral follicles. The aims of this study were (1) to use a highly specific monoclonal antibodies to AMH and inhibin B to measure serum concentrations of these hormones in 2 groups of women with PCOS: those with PCO and oligo- or amenorrhoea (PCO-oligo, n=44) and (for the first time) those with PCO who have regular cycles (PCO-reg, n=44) and (2) to determine, by multivariate analysis, the clinical and endocrine variables that independently influence AMH concentrations. The control group comprised 32 women with normal ovaries and regular cycles. AMH levels (median and [range]) in both PCO-oligo (3.40 [0.05–11.4] ng/ml) and PCO-reg (2.41 [0.59–8.03]) were significantly different from control (0.81 [0.08–3.59]) (p<0.0001; Kruskal-Wallis; Dunn’s post test: PCO-oligo vs control p<0.001; PCO-reg vs control p<0.001; PCO-oligo vs PCO-reg p>0.05). In contrast, there were no significant differences between the groups in inhibin B concentrations. Multivariate analysis indicated that only these factors independently affected AMH levels: age (p=0.045), LH (p=0.023), inhibin B (p=0.005) and, most significantly, the type of ovary (p<0.0001). In summary, serum AMH levels are elevated in both ovulatory and anovulatory women with PCO whereas inhibin B levels are similar between the groups. Thus the presence of PCO, irrespective of cycle history, appears to be the most important determinant of serum AMH concentrations.