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Updated: Feb 15, 2026

Author Spotlight: Investigating the Mechanisms and Inducing Models of Polycystic Ovary Syndrome
Published on: July 5, 2024
Letrozole versus clomiphene citrate in polycystic ovary syndrome: a meta-analysis of randomized controlled trials
Shifu Hu1, Qiong Yu2, Yingying Wang1
1Family Planning Research Institute, Tongji Medical College, Huazhong University of Science and Technology, Hangkong Road 13, Wuhan, 430030, Hubei, China.
Purpose:
Polycystic ovary syndrome (PCOS) is a common endocrine disturbance affecting women in the reproductive age group. The present study aimed to compare the effects of letrozole (LE) and clomiphene citrate (CC) for ovulation induction in women with PCOS.
Methods:
The PUBMED, Web of Science, and EMBASE databases were screened systematically for randomized controlled trials (RCTs) published from database inception to July 2017.
Results:
Eleven RCTs involving 2255 patients were included, and data were independently extracted and analyzed using 95% risk ratios (RRs) and confidence intervals (CIs) based on a random- or fixed-effect model (as appropriate). Meta-analyses of nine RCTs comparing LE and CC ovulation induction, followed by timed intercourse, indicated that the former significantly increased the ovulation rate (RR = 1.18; 95% CI 1.03-1.36, P = 0.01), pregnancy rate (RR = 1.34; 95% CI 1.09-1.64, P = 0.006), and live birth rate (RR = 1.55; 95% CI 1.28-1.88, P < 0.00001). However, LE and CC did not differ significantly in terms of the multiple pregnancy and abortion rates. Furthermore, LE for ovulation induction significantly improved the pregnancy rate after IUI.
Conclusion:
LE is superior to CC for ovulation induction in patients with PCOS.
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