Hyperinsulinemia does not influence androgens/estrogens ratio in patients with polycystic ovarian syndrome

The ratio of androgens to estrogens in patients with polycystic ovarian syndrome (PCOS) and controls was evaluated in order to investigate whether hyperinsulinemia might induce hyperandrogenemia by decreasing androgen catabolism.

Forty women were divided into four groups according to the presence of PCOS, insulin resistance, and normal or abnormal body mass index (BMI); each group consisted of 10 women. Group I comprised patients with PCOS, insulin resistance, and abnormal BMI. Group II consisted of patients with PCOS, without insulin resistance, and with normal BMI. Group III consisted of healthy women (controls) with abnormal BMI. Group IV consisted of healthy women with normal BMI.

We found that: (1) the mean fasting insulin levels of groups II, III, and IV were significantly lower than those of group I (P < .001); (2) serum testosterone levels were significantly lower in groups III and IV than in group I and II; (3) there were no significant differences in serum estradiol and estrone levels between women of all groups; (4) women of groups III and IV had significantly lower ratios of testosterone to estradiol at time 0 compared to patients of groups I and II.

Our results support the view that since hyperinsulinemia induces hyperandrogenism, the increase of androgens should not be attributed to the decrease of androgen catabolism.