The efficacy of letrozole supplementation for medical abortion: a meta-analysis of randomized controlled trials

The efficacy of letrozole supplementation for medical abortion remains controversial. We conduct a systematic review and meta-analysis to explore the influence of letrozole supplementation for medical abortion.

We searched PubMed, Embase, Web of Science, EBSCO, and Cochrane Library databases through October 2018 for randomized controlled trials (RCTs) assessing the effect of letrozole supplementation for medical abortion. This meta-analysis is performed using the random-effect model.

Six RCTs involving 555 patients are included in the meta-analysis. Overall, compared with control group for pregnant women, letrozole supplementation shows significantly increased complete abortion (RR = 1.38; 95% CI = 1.07-1.78; p = .01), and decreased estradiol (std. MD = -2.86; 95% CI = -4.45 to -1.27; p = .0004), but has no remarkable effect on induction-abortion time (std. MD = -1.03; 95% CI = -2.99-0.93; p = .30), progesterone (std. MD = 0.02; 95% CI = -0.30-0.34; p = .89), vaginal hemorrhage (std. MD = 1.84; 95% CI = 0.05-70.90; p = .74), nausea and vomiting (std. MD = 073; 95% CI = 0.44-1.21; p = .22).

Letrozole supplementation provides benefits to medical abortion in pregnant women.