Treating Hypertension During Pregnancy: Benefits Seem to Outweigh Risks

Eleanor Bimla Schwarz, MD, MS reviewing Magee LA et al. N Engl J Med 2015 Jan 29.

Fetal and neonatal outcomes were not adversely affected by a maternal diastolic target of 85 mm Hg.

Almost 10% of pregnancies are affected by hypertension, yet many clinicians remain reluctant to prescribe antihypertensives during pregnancy. To evaluate the effects of “less-tight” (diastolic target, 100 mm Hg) versus “tight” (diastolic target, 85 mm Hg) blood pressure (BP) control during pregnancy, researchers conducted an open-label multicenter trial in which 987 pregnant women were randomly assigned to either target. Participants had nonsevere, nonproteinuric preexisting hypertension or gestational hypertension (diastolic BP, 90–105 mm Hg without medication or 85–105 mm Hg with medication) and singleton pregnancies (gestation, 14 weeks 0 days to 33 weeks 6 days).

In both groups, labetalol was the most commonly used antihypertensive, but more women required medication to reach the tighter goal. Rates of pregnancy loss, low birth weight, and need for neonatal intensive care were similar between groups. However, significantly fewer women treated with tighter control developed abnormally low platelet counts (1.6% vs. 4.3%) or elevated liver function tests (1.8% vs. 4.3%), with a trend toward less need for blood transfusion (1.6% vs. 3.2%).

Citation(s):

Magee LA et al. Less-tight versus tight control of hypertension in pregnancy. N Engl J Med 2015 Jan 29; 372:407.