Treatment of mild and chronic hypertension during pregnancy yields positive results

In pregnant women with mild and chronic hypertension, a treatment strategy aimed at lowering blood pressure below 140/90 mmHg was associated with better pregnancy outcomes than a strategy that treated only severe hypertension without compromising fetal growth.

This is what researchers from the United States wrote in the New England Journal of Medicine. They conducted a randomized, open-label, multicenter trial in which a total of 2,408 pregnant women with one child, gestational age of less than 23 weeks with moderate and chronic hypertension (<160/100 mmHg) were randomized to antihypertensive drugs (recommended tags for use during pregnancy), or without treatment (unless severe hypertension occurs).

The primary outcome was a composite measure of pre-eclampsia with severe symptoms, medically indicated preterm birth (<35 weeks’ gestation), placental abruption, and fetal or neonatal death. This outcome was less common in the treatment group (30.2%) than in the control group (37.0%), with an adjusted hazard ratio of 0.82 (95% CI 0.74–0.92; P<0.001). The safety outcome, defined as birth weight less than the 10th percentile of gestational age, was not significantly more common in the treatment group (11.2%) than in the control group (10.4%; hazard ratio 1.04; 95% CI 0.82–1.31, p = 0.76).

Furthermore, serious maternal complications occurred in 2.1 and 2.8% (0.75; 95% CI 0.45-1.26) and serious neonatal complications in 2.0 and 2.6% (0.77 95% CI 0.45-1.30). The risk of pre-eclampsia (0.79; 95% CI 0.69-0.89) and preterm birth (0.87; 95% CI 0.77-0.99) was lower in the treated group than in the control group.