Aspirin (100 mg) used for prevention of pre-eclampsia in nulliparous women: the Essai Régional Aspirine Mère-Enfant study (Part 1).

OBJECTIVE: To reduce the incidence of pre-eclampsia in nulliparous women, in accordance with the suggestion of a recent meta-analysis that low dose aspirin might decrease this incidence by more than half if used early enough in and at a sufficient dose during pregnancy (more than 75 mg).

DESIGN: Multicentre randomised double-blinded placebo-controlled trial.

SETTING: Twenty eight centres in Northern of France and one in Belgium.

POPULATION: Three thousand and two hundred ninety-four nulliparous women recruited between 14 and 20 weeks.

METHODS: Randomisation to either 100 mg aspirin or placebo daily from inclusion through 34 weeks.

MAIN OUTCOME MEASURES: Preeclampsia was defined as hypertension (> or =140 and or 90 mmHg) associated with proteinuria (> or =0.5 g/L).

RESULTS: The aspirin (n = 1644) and placebo (n = 1650) groups did not differ significantly in the mothers' incidence of pre-eclampsia (28 of 1632 [1.7%] vs 26 of 1637 [1.6%]; relative risk, RR, 1.08, 95% CI 0.64-1.83), hypertension, HELLP syndrome or placental abruption, or in the children's incidence of perinatal deaths or birthweight below the 10th centile. The incidence of babies with birthweight below the third centile was significantly higher in the aspirin group, with no explanation. The incidence of maternal side effects was higher in the aspirin group, principally because of a significantly higher rate of haemorrhage.

CONCLUSIONS: Aspirin at a dose of 100 mg does not reduce the incidence of pre-eclampsia in nulliparous women. Aspirin (100 mg) is associated with an increase in bleeding complications.