Metformin therapy improves ovulatory rates, cervical scores, and pregnancy rates in clomiphene citrate-resistant women with polycystic ovary syndrome.

Objective: To evaluate the effect of metformin therapy on hyperandrogenism, insulin resistance, cervical scores, ovulation, and pregnancy rates in clomiphene citrate-resistant women with polycystic ovary syndrome (PCOS).

Design: Prospective, randomized, double-blind, placebo-controlled study.

Setting: Infertility clinic of a tertiary referral center.

Patient(s): Fifty-six women with clomiphene citrate-resistant PCOS.

Intervention(s): Two cycles of oral metformin therapy (850 mg, twice daily) in group I and placebo therapy (twice daily) in group II. Clomiphene citrate (100 mg/day) on cycle days 3-7 of the second cycle in both groups.

Main Outcome Measure(s): Insulin, T, DHEAS, FSH, LH, body mass index (BMI), waist-to-hip ratio, endometrial thickness, cervical score, ovulation, and pregnancy rates in clomiphene-induced cycles after metformin therapy.

Result(s): Metformin therapy resulted in a significant decrease in total T, LH level, LH/FSH ratio, insulin resistance, and mean BMI. No difference in waist-to-hip ratio, DHEAS level, and fasting insulin level was observed. Clomiphene citrate induction resulted in higher ovulation rates and thicker endometrium in the metformin group than in the placebo group. There was higher cumulative pregnancy rate in the metformin group; however, there was no significant difference in the pregnancy rate between the two groups.

Conclusion(s): Metformin therapy not only decreases hyperandrogenism and insulin resistance but also improves ovulation rates, cervical scores, and pregnancy rates in clomiphene citrate-resistant women with PCOS.