Antiplatelet drugs for prevention of pre-eclampsia and its consequences: systematic review

Objective To assess the effectiveness and safety of antiplatelet drugs for prevention of pre-eclampsia and its consequences. Design Systematic review. Data sources Register of trials maintained by Cochrane Pregnancy and Childb irth Group, Cochrane Controlled Trials Register, and Embase. Included studi es Randomised trials involving women at risk of pre-eclampsia, and its comp lications, allocated to antiplatelet drug(s) versus placebo or no antiplate let drug. Main outcomes measures Pre-eclampsia, preterm birth, fetal or neonatal deat h, and small for gestational age baby. Studies were assessed for quality of concealment of allocation and losses to follow up. Results 39 trials (30 5 63 women) were included, and 45 trials ( > 3000 women) excluded. Use of ant iplatelet drugs was associated with a 15% reduction in the risk of pre-ecla mpsia (32 trials, 29 331 women; relative risk 0.85, 95% confidence interval 0.78 to 0.92; number needed to treat 100, 59 to 167). There was also am 8% reduction in the risk of preterm birth (23 trials, 28 268 women; 0.92, 0.8 8 to 0.97; 72, 44 to 200), and a 14% reduction in the risk of fetal or neon atal death (30 trials, 30 093 women; 0.86, 0.75 to 0.98; 250, 125 to > 10 0 00) for women allocated antiplatelet drugs. Small for gestational age babie s were reported in 25 trials (20 349 women), with no overall difference bet ween the groups (relative risk 0.92, 0.81 to 1.01). There were no significa nt differences in other measures of outcome. Conclusions Antiplatelet drugs, largely low dose aspirin, have small to mod erate benefits when used for prevention of pre-eclampsia.