Response of IGF and IL-6 to Ovarian Stimulation in PCOS and Normal Women

The objective of the present study was to investigate the response patterns of insulin-like growth factors (IGFs) and interleukin-6 (IL-6) to ovarian stimulation within 24 h in patients with polycystic ovary syndrome (PCOS) in comparison with normally ovulating women. This controlled prospective clinical study involved 60 women who attended an infertility clinic. For the induction of the ovarian stimulation, fifty-two patients with PCOS and eight control cases were injected with human menopause gonadotropin (hMG) and human chorionic gonadotropin (hCG) during the early follicular phase of the natural or induced menstrual cycle. The blood was sampled before (0 h) and 6, 12, 18, and 24h after the stimulation. Serum levels of estradiol (E2), IGF-I, IGF-II and IL-6 were measured by radioimmunoassay. A significant decrease in serum IGF-II at 12 h was observed after a mixture of hMG and hCG was administered in patients with polycystic ovaries (PCO) including the typical PCOS group and the PCO + OA group (accumulated p < 0.05), while normal women presented a slight decrease (accumulated p < 0.1) 18 h after the stimulation. Moreover, all the groups had similar serum levels of IL-6 and IGF-I at all time points. An increase in serum E2 occurred coincident with a decrease in IGF-II in all the groups except the ovarian hyperandrogenism patients (HA + OA group). Serum IGF-II levels, which appeared to be negatively correlated with elevated E2, statistically decreased in PCO patients early after hMG and hCG administration when monitored for 24 h, while no such changes were observed in IGF-I and IL-6.