Adding low-dose aspirin to calcium does not prevent pre-eclampsia in high-risk pregnancies

Treatment with low-dose aspirin, when added to calcium, early in pregnancy does not appear to provide any benefit in terms of reducing the incidence of pre-eclampsia as well as caesarean section or other important neonatal outcomes in high-risk women, according to a study.

A total of 266 women who were taking calcium at 1 g/day for being at high risk of pre-eclampsia were enrolled at several health centres and a tertiary hospital in Blantyre, Malawi. These women were randomly assigned to receive either low-dose aspirin (150 mg/day) or placebo from 12 to 16 weeks until 34 weeks of gestation.

Researchers performed intention-to-treat and adherence analyses to assess the primary endpoint of pre-eclampsia.

Of the women, 42 had pre-eclampsia (15.8 percent) and six had eclampsia (2.3 percent). Compared with placebo, treatment with low-dose aspirin had no significant effect on the incidence of pre-eclampsia in high-risk pregnancies (19.3 percent vs 12.2 percent; adjusted odds ratio, 1.16, 95 percent confidence interval, 0.41–3.41; p=0.781).

Likewise, secondary maternal and neonatal outcomes did not significantly differ between the low-dose aspirin and placebo groups.

The overall adherence rate in the study was 69 percent.

Pre-eclampsia continues to be a leading contributor to maternal and neonatal mortality and morbidity, and the findings of this study demonstrate that using low-dose aspirin in combination with calcium falls short of reducing its burden in high-risk pregnancies, the researchers said.