Hyperinsulinemia in PCOS. Possible role in the determination of the ovary response to gonadotrophins

In order to evaluate the relationships between circulating insulin levels and ovarian response to exogenous gonadotrophins therapy in polycystic ovarian disease, we studied 52 conservative cycles in 34 patients affected with polycystic ovary syndrome (PCOS) and treated with FSH. All patients underwent an oral glucose tolerance test (OGTT) (75 gr) during their follicular phase. In the 3rd-4th day of each cycle, all patients were treated with FSH (150 IU/day). Ovarian response was monitorited by ultrasound, hCG (5000 IU) was administered when the size of the follicle reached a diameter of 18 mm. Based on insulinemic response to OGTT, patients were classified in normoinsulinemic (14) and hyperinsulinemic (20). Normoinsulinemic patients were studied for 21 cycles and hyperinsulinemic patients for 31 cycles. No significant differences were observed between the two groups in terms of basal values of ovarian volumes and maximal estradiol levels. Ovarian hyperstimulation syndrome (OHSS) incidence was significantly higher in the hyperinsulinemic group. These data suggest that the finding of hyperinsulinemia in PCO patients, should lead to a greater caution in the use of gonadotrophins for ovarian stimulation in order to prevent the establishment of the OHSS.