Serum inhibin A concentration in women with polycystic ovarian syndrome and the correlation to ethnicity, androgens and insulin resistance

A prospective case-series in an academic hospital clinic was performed to determine whether there is a relationship between polycystic ovarian syndrome (PCOS) and ethnicity. Also, serum inhibin A concentrations were compared between PCOS and normal-ovulatory women. The possibility of a correlation between inhibin A, androgens and insulin resistance in PCOS women was evaluated. Serum inhibin A concentrations were measured in anovulatory PCOS patients (n = 32) and in control women of reproductive age (n = 16). Statistical analysis was performed using the Mann–Whitney U-test. Serum concentrations of inhibin A, follicle-stimulating hormone, LH, prolactin, thyroid-stimulating hormone, fasting glucose, insulin, testosterone, 17-hydroxyprogesterone (17-OHP) and dehydroepiandrosterone sulphate (DHEAS) were measured. Inhibin A concentrations were significantly lower (4.5 ± 4.8 pg/ml) when compared with the control group (13.2 ± 14.4 pg/ml; P = 0.003) and were not significantly different between Hispanic and Caucasian women diagnosed with PCOS. There was no correlation between inhibin A concentrations and insulin, testosterone, free testosterone, 17-OHP, or DHEAS concentrations. In PCOS women, inhibin A concentrations are similar between Hispanic and Caucasian women; however, women with PCOS, regardless of ethnicity, have a lower inhibin A concentration compared with normal-ovulatory women. No correlation was observed between inhibin A androgens and insulin resistance in women diagnosed with PCOS.