Effect of ovarian suppression on glucose metabolism of young lean women with and without ovarian hyperandrogenism

Gonadal steroids are believed to influence glucose metabolism, oestrogens i nducing an improvement and androgens or progestins a deterioration. At base line and after 3 months of ovarian suppression with a gonadotrophin-releasi ng hormone analogue (GnRHa: goserelin depot 3.75 mg/28 days), glucose metab olism was evaluated in eight lean women affected by ovarian hyperandrogenis m (PCOS) and six age-weight-matched non-hyperandrogenic women (controls) by using both an oral glucose tolerance test (75 g; OGTT) and the minimal mod el method. The latter method allows calculation of peripheral insulin sensi tivity (Si) and glucose dependent glucose utilization (Sg). In PCOS, higher fasting concentrations (P < 0.05) of insulin and C-peptide, and lower Sg ( P < 0.05) and Si (P < 0.01) were found. GnRHa did not significantly modify glucose metabolism of controls, while in women with PCOS it decreased fasti ng glucose (P < 0.05) and significantly increased Si (P < 0.03) up to contr ol values. The present data indicate that strong suppression of ovarian act ivity improves Si in lean women with PCOS, while it is without relevant eff ects on glucose metabolism of non-hyperandrogenic women.