Preterm preeclampsia is an important cause of maternal and perinatal
death and complications. In this multi-centre, double-blind, placebo-controlled trial published in the NEJM
women with singleton pregnancies who were at high risk for preterm preeclampsia were randomly assigned to receive low-dose aspirin (150 mg
per day), or placebo, from 11 to 14 weeks of gestation until 36 weeks of gestation. Preterm preeclampsia occurred in 1.6% of participants
in the low-dose aspirin group, compared to 4.3% in the placebo group. Adherence was good, and there were no significant between-group
differences in the incidence of neonatal adverse outcomes or other adverse events.