Study Finds Hypertension Treatment During Pregnancy Does Not Put Unborn At Risk

Giving pregnant women hypertension treatment before it becomes severe may lead to better pregnancy outcomes, researchers found.

New research highlights the benefits of treating high blood pressure during pregnancy, even mild high blood pressure, indicating that it reduces the risk of delivery complications and problems for the newborn.

Women who were actively treated for high-blood pressure and given antihypertensive medications had a lower risk of suffering from preeclampsia, experiencing complications during delivery and were less like to have a child with low birth weight, according to findings published this month in The New England Journal of Medicine.

Researchers from the University of Alabama, Birmingham, conducted a multi-center, randomized trial involving pregnant women affected by mild chronic hypertension. If the fetus was at a gestational age of less than 23 weeks, the women received medication to reduce their blood pressure numbers to below 140/90 mm Hg. The other half were not given antihypertensive medications unless they suffered from severe hypertension greater than 160 mm Hg systolic.

A total of 2,400 women were enrolled in the trial at medical centers across the U.S. All the women had mild chronic hypertension.

According to the data, receiving blood pressure medication reduced a woman’s risk of suffering serious complications. Those who received active treatment had a 30% risk of suffering side effects like preeclampsia or dysfunction to their organs, compared to a 37% risk among those who did not receive medication.

Roughly 24% of women on the strict regimen of blood pressure medication developed preeclampsia, a life-threatening condition marked by the sudden onset of decreased blood pressure and serious complications. Comparatively, 31% of women in the no-medication group developed preeclampsia.

Women faced a slightly higher risk of maternal complications if they didn’t take blood pressure medication. Those on medication had a 2% risk while those not on the medication had a 3% risk.

Similarly, the risk of preterm birth was 28% among those that took hypertension medications, compared to 31% among those who were not on medication. Researchers also noted those who received medication had an 11% reduced risk of small for gestation age birth weight below the 10th percentile, compared to 10% in the group that did not receive medication.

The United States has one of the highest maternal death rates among developed, high-income countries, largely linked to pregnancy and childbirth complications. Findings like this, point to some of the reasons why the maternal death rate may be so high.

A previous study indicated offering pregnant women low-dose aspirin may be a simple way to prevent preeclampsia. More than 85% of pregnant women should be prescribed low-dose aspirin to prevent pregnancy complications.

“In pregnant women with mild chronic hypertension, a strategy of targeting a blood pressure of less than 140/90 mm Hg was associated with better pregnancy outcomes than a strategy of reserving treatment only for severe hypertension, with no increase in the risk of small-for-gestational-age birth weight,” wrote study authors.