Low-Dose Aspirin for Preventing Preeclampsia and Its Complications: A Meta-Analysis.

Low-dose aspirin (LDA) is thought to prevent preeclampsia in high-risk pregnancy, but it is not universally used out of concern for its efficacy and safety. The authors meta-analyzed 29 randomized controlled trials (RCTs) to evaluate LDA for preventing preeclampsia and its complications. LDA can reduce the incidence of preeclampsia (odds ratio [OR], 0.71; 95% confidence interval [CI], 0.57-0.87), severe preeclampsia (OR, 0.37; 95% CI, 0.23-0.61), preterm birth (OR, 0.81; 95% CI, 0.75-0.88), and intrauterine growth restriction (IUGR) (OR, 0.80; 95% CI, 0.71-0.90). LDA is more effective in reducing incidence of preeclampsia or IUGR if used before 16 gestational weeks than if used later. LDA increases the incidence of placental abruption (OR, 1.35; 95% CI, 1.05-1.73) but not other major complications. The available evidence suggests that LDA is effective in preventing preeclampsia, preterm birth, and IUGR in high-risk pregnancies without posing a major safety risk to mothers or fetuses.