The effect of metformin treatment to ovarian response in cases with PCOS.

Objective: To examine the effect of metformin therapy on ovarian response in clomiphene-resistant PCOS patients.

Design: Randomized prospective study.

Setting: Zeynep Kamil Hospital IVF Center.

Patients: Thirty-two female PCOS patients with clomiphene citrate resistance.

Interventions: Test group A received 2x850 mg/day metformin therapy for 8 weeks, followed by gonadotropin induction. Only gonadotropin induction was applied to Control group B.

Main Outcome Measures: Total gonadotropin dosage, duration of gonadotropin therapy, estradiol level on HCG-day, number of follicles with >or=16 mm diameter, number of cases with hyperstimulation development, number of cancelled cycles, endometrial thickness on HCG-day, pregnancy outcome, multiple pregnancy rate.

Results: The total gonadotropin doses given to metformin-study group was significantly lower than the control group. In addition, duration of therapy, HCG level, plasma estradiol level on HCG-day in the study group was significantly lower than in the control group.

Conclusions: Metformin therapy has led to a higher pregnancy outcome, as well as to a decrease in hyperstimulation risk, cycle cancellations, and multiple pregnancy rates with a lower gonadotropin dosage.