- In women with polycystic ovary syndrome (PCOS) and infertility, letrozole (Femara) is associated with improved live birth and clinical pregnancy rates compared with clomiphene citrate (CC; Clomid, Serophene), whereas adding metformin to CC may increase clinical pregnancy rates, according to a systematic review and meta-analysis.
Why this matters
- This meta-analysis suggests that letrozole may be the preferred treatment choice for women with PCOS and infertility.
- Letrozole was associated with improved live birth rates (3 studies, risk ratio [RR], 1.43; 95% CI, 1.17-1.75), improved clinical pregnancy rates (6 studies, RR, 1.45; 95% CI, 1.23-1.70), improved ovulation (RR, 1.13; 95% CI, 1.07-1.20), and reduced time to pregnancy (6 studies, HR, 1.72; 95% CI, 1.38-2.15) compared with CC.
- Baseline serum total testosterone levels were associated with the treatment effects of letrozole on live birth (RR, 1.29; 95% CI, 1.01-1.65).
- CC plus metformin was associated with improved clinical pregnancy rates (8 studies, RR, 1.18; 95% CI, 1.00-139) and reduced time to pregnancy (7 studies, HR, 1.25; 95% CI, 1.00-1.57) compared with CC alone.
- 3962 women with PCOS from 20 randomized controlled trials were included in the meta-analysis.
- Funding: Australian National Health and Medical Research Council.
- Heterogeneity between included studies.