Comparison of clomiphene citrate and letrozole for ovulation induction in women with polycystic ovary syndrome: a prospective randomized trial.

To compare the therapeutic efficacy of clomiphene citrate (CC) and letrozole (LE) on ovulation, pregnancy, and live birth in women with polycystic ovary syndrome (PCOS); and to ensure if LE can replace CC as the first-line therapy for ovulation induction in these women. This is a prospectively, randomized, controlled trial in the tertiary hospital. Two-hundred and sixty-eight anovulatory PCOS patients were treated by CC or CC plus metformin and LE or LE plus metformin for three continuous cycles or conception; their ovulation rates, pregnancy rates, and live birth rates were calculated and compared. No significant difference was noted among the four groups regarding to the baseline data of clinical manifestations, serum sex hormone levels, and serum insulin levels. A total of 240 patients completed the therapies. The ovulation rate was significantly higher in the group LE than the group CC; however, no significant difference was noted between the groups LE and CC, CC, and CC + MET, or LE and LE + MET in the pregnancy rate, abortion rate, and live birth rate. No birth defect was found in the total of 63 newborns. CC regimen was still recommended to be the first-line therapy of ovulation induction for PCOS.