Letrozole versus Clomiphene Citrate for Ovulation Induction in Women with Polycystic Ovary Syndrome: A Systematic Review

Abstract

Introduction: Polycystic Ovary Syndrome (PCOS) is the most common cause of anovulatory infertility. Clomiphene citrate has been the first-line treatment, but the aromatase inhibitor letrozole has emerged as a promising alternative. This review compares their efficacy.

Methods: We conducted a search for RCTs comparing letrozole to clomiphene citrate for ovulation induction in infertile women with PCOS. The primary outcome was the live birth rate.

Results: The meta-analysis of 15 RCTs demonstrated that letrozole was associated with a significantly higher live birth rate compared to clomiphene citrate. Letrozole also resulted in a higher ovulation rate per cycle. The incidence of multiple pregnancies was similar between the two groups.

Discussion: Letrozole appears to be more effective than clomiphene, likely due to its monofollicular stimulation and more favorable effects on the endometrium. These findings support a change in clinical practice.

Conclusion: Letrozole is superior to clomiphene citrate and should be considered the first-line agent for ovulation induction in women with PCOS.