Blood pressure treatment during pregnancy is safe and may lower the mother's risk for severe hypertension, according to a new scientific statement from the American Heart Association (AHA).
The statement, published in Hypertension, included a detailed analysis of studies that have focused on high blood pressure during pregnancy. According to the AHA, hypertension is the second leading cause of maternal death around the world.
“For decades, the benefits of blood pressure treatment for pregnant women were unclear," Vesna D. Garovic, MD, PhD, writing group chair and chair of the division of nephrology and hypertension at Mayo Clinic, said in a prepared statement. “And there were concerns about fetal well-being from exposure to antihypertensive medications. Through our comprehensive review of the existing literature, it is reassuring to see emerging evidence that treating high blood pressure during pregnancy is safe and effective and may be beneficial at lower thresholds than previously thought. Now, we have the current statement focused on hypertension during pregnancy to help inform optimal treatment and future research.”
The United States has one of the highest hypertensive-related maternal mortality rates compared with other high-income countries, according to the statement. In fact, cardiovascular disease is responsible for almost half of all maternal fatalities in the U.S. while pregnancy-related stroke hospitalizations rose more than 60% from 1994 to 2011.
“Given the rising number of cases of hypertension during pregnancy, together with hypertension-related complications, the problem has become a public health crisis, particularly among women from racially and ethnically diverse backgrounds,” Garovic said.
While there is a lack of consensus regarding when to start hypertension treatment during pregnancy due to concerns over how medications may affect the fetus, healthcare experts recommend initiating treatment when blood pressure readings during pregnancy range from 140/90 mm Hg (Canadian guidelines) to 160/110 mm Hg (U.S. guidelines).
“Future studies should address whether lowering the threshold for treating hypertension during pregnancy might allow for safe and timely blood pressure control and avoid a rushed delivery because of uncontrolled hypertension,” Garovic said.
The AHA scientific statement supports recent research suggesting that lifestyle changes prior to and during pregnancy may potentially improve maternal and fetal outcomes.
For example, dietary changes before and during pregnancy can limit weight gain and improve pregnancy outcomes. Also, exercise may reduce the risk of gestational hypertension risk by nearly 30% and the risk of preeclampsia by nearly 40%.
The statement's writing group also note that there is growing evidence suggesting hypertension after delivery may be linked with significant maternal health problems. Physicians may want to consider individualized treatment decisions that take risk factors and patient preferences into consideration.
Read the full scientific statement here.