In pregnant women with mild, 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.
That is what researchers from the United States write in the New England Journal of Medicine. They conducted an open-label, multicenter, randomized trial in which a total of 2,408 women pregnant with one baby, with a gestational age <23 weeks and with mild, chronic hypertension (<160/100 mmHg) were randomized to antihypertensive drugs (recommended for use during pregnancy), or to no treatment (unless severe hypertension developed).
The primary outcome was a composite measure of preeclampsia with severe symptoms, medically indicated preterm birth (< 35 weeks gestation), placental abruption, 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 risk ratio of 0.82 (95% CI 0.74-0.92; p < 0.001). The safety outcome, defined as a birth weight below the tenth percentile for gestational age, was not significantly more common in the treatment group (11.2%) than in the control group (10.4%; risk 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). Both the risk of preeclampsia (0.79; 95% CI 0.69-0.89) and preterm birth (0.87; 95% CI 0.77-0.99) were lower in the treated group than in the control group.
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