Objective. To investigate the ovarian activity before and after gonadal suppression with GnRH-analog in patients with PCO, hyperandrogenism, hyperinsulinism and ancathosis nigricans.

Design:

Controlled clinical study.

Setting:

Tertiary academic medical center.

Patients:

Six patients with clinical findings of PCO, hirsutism and acanthosis nigricans. Interventions. Morning blood samples in the follicular phase to determine the seteroid levels, glucose and insulin curve, comparing to a control group. Administration for 2 consecutive months of a GnRH-analog, comparing, in the study group, the free testosterone levels before and after ovarian suppression. Main Outcome Measure. Determination of insulin levels in PCO, hirsutism and acanthotic patients and the free-testosterone levels before and after gonadal suppression. Results. Insulin levels were significantly higher in the study group when compared to normal women during the glycemic test. We also found a significant decrease in the free-testosterone levels after 2 months of gonadal suppression with GnRH-analog when compared to the initial time. Conclusions. Patients with PCO, hirsutism and acanthosis nicrigans present high levels of in sulin, suggesting an ovarian hyperesponsiveness, which is not sustained when gonadotrophic blockage was achieved.