Efficacy predictors for metformin and clomiphene citrate treatment in anovulatory infertile patients with polycystic ovary syndrome

OBJECTIVE: To evaluate ovulation and pregnancy predictors in infertile polycystic ovary syndrome (PCOS) patients who received clomiphene citrate (CC) and metformin as first-line ovulation inductors. DESIGN: Prospective controlled study. SETTING: Departments of Obstetrics and Gynecology, Universities Magna Graecia of Catanzaro and Federico II of Naples, Italy. PATIENT(S): Eighty infertile anovulatory PCOS patients allocated in two groups matched for body mass index (BMI) and age. INTERVENTION(S): Metformin (1700 mg/day for 6 months) or CC (50 mg/day, increasing doses up to 250 mg/day). MAIN OUTCOME MEASURE(S): Baseline clinical and biochemical parameters categorized according to interventions response. RESULT(S): The BMI was statistically significantly lower in patients who ovulated under both treatments. Insulin sensitivity indexes were statistically significantly worse in patients who ovulated under metformin and statistically significantly better in patients who ovulated under CC. Androgen levels and free androgen index (FAI) were statistically significantly lower in ovulatory patients than in anovulatory ones who received CC. Age, BMI, infertility duration, and insulin sensitivity indexes were statistically significantly different between patients who achieved and those who did not achieve a pregnancy under both treatments. Androgens levels and FAI were statistically significantly lower in patients who achieved a pregnancy under CC. CONCLUSION(S): Insulin-resistant PCOS patients with low BMI are more likely to respond to metformin whereas CC treatment is more effective in less hyperandrogenic and insulin-resistant PCOS patients with low BMI.