A randomised trial of low dose aspirin for primiparae in pregnancy. The Jamaica Low Dose Aspirin Study Group

ABSTRACT

OBJECTIVE: To investigate whether low dose aspirin medication given to primiparous women provides benefit in preventing pre-eclampsia or intrauterine growth retardation. DESIGN: Randomised double-blind controlled trial of low dose aspirin and placebo in pregnancy. POPULATION Residents of the parishes of Kingston and St. Andrew, Jamaica; 6275 primiparae enrolled between 12 and 32 weeks of gestation. MAIN OUTCOME MEASURES: Hypertensive disorders of pregnancy (including pre-eclampsia and eclampsia), preterm delivery, and low birthweight. In addition, to assess whether enrollment early, rather than late had more beneficial effect. Possible adverse effects on the woman and her infant were monitored. RESULTS: Of enrolled primiparae, 97 percent were followed throughout pregnancy. There were no differences between those on aspirin and those on placebo in the development of hypertensive disorders (e.g. for a rise in diastolic pressure of 25 mmHg the odds ratio [OR] was 1.02 [95 percent CI 0.86-1.21]; for proteinuric pre-eclampsia OR 1.15 [95 percent CI 0.92-1.44]; eclampsia OR 0.82 [95 percent CI 0.44-1.53]; except for oedema which was significantly less prevalent in those on aspirin (OR 0.85 [95 percent CI 0.75-0.96]). Women on aspirin were no significantly less likely to deliver preterm (OR 0.93 [95 percent CI 0.79-1.09]) or have a larger fetus (mean birthweight difference 18 g [95 percent CI -9 to 45]). They were, however significantly more likely to suffer from bleeding disorders antenatally, intrapartum and postpartum for postpartum haemorrhage OR 1.40 (95 percent CI 1.13-1.73). CONCLUSION: This trail shows that low dose aspirin has no consistent beneficial effect in primiparae(AU)