Growing numbers of pregnant women are taking antihypertensive drugs that may harm themselves or their babies, according to a new study published in Hypertension.
Brian Bateman and colleagues analyzed Medicaid data from more than 1.1 million pregnant women. Overall, 4.4% of the women received antihypertensive medications at some point during their pregnancy. From 2000 to 2007 the use of antihypertensive drugs increased from 3.5% to 4.9%. This increase, according to the authors, is “consistent with the rising rates of chronic hypertension and gestational hypertension… which in turn may reflect rising rates of obesity and advanced maternal age in US parturients.”
Exposure to antihypertensive drugs occurred in 1.9% of women during the first trimester, 1.7% during the second trimester, and 3.2% during the third trimester. ACE inhibitors, which are contraindicated in late pregnancy, were used in 4.9% of women who used antihypertensive medications in the second trimester and 1.1% in the third trimester. The authors said that automatic refills and the “prescribing physicians’ failure to ask about the possibility of pregnancy are two plausible explanations.”
About half of women who had been taking antihypertensive drugs prior to their pregnancy discontinued drug treatment during the first or second trimester. According to the authors, although antihypertensive therapy for mild-to-moderate hypertension can prevent progression to severe hypertension it is unknown whether it can reduce the risk of pregnancy complications, including placental abruption, fetal demise, superimposed preeclampsia, preterm birth, or maternal morbidity.
“While we know high blood pressure, or hypertension, occurs in about 6 percent to 8 percent of all pregnancies, we know little about how women and their doctors treat the condition,” said Bateman, in an AHA press release.
The authors pointed out that “there is virtually no data on the comparative effectiveness and safety of the different treatment options for hypertension” in pregnant women. “Research investigating the comparative safety and efficacy of antihypertensive therapy in pregnancy is urgently needed to define the optimal approach to therapy.”
Republished with permission from CardioExchange, a NEJM group publication.
Here is the press release from the AHA:
More pregnant women taking high blood pressure drugs, yet safety unclear
- Nearly 5 percent of pregnant women take high blood pressure drugs — some that may have harmful effects — and the number is increasing.
- Research is urgently needed on which antihypertensive drugs are safe during pregnancy and how to use them.
- Antihypertensive drug use increased from 3.5 percent to 4.9 percent between 2000 and 2006.
- Antihypertensive drug users were older than non-users, more likely to have diabetes or kidney disease, and more likely to be Caucasian or African-American than Hispanic or Asian.
- Nearly 2 percent of pregnant women filled prescriptions for these drugs during the first trimester; 1.7 percent during the second trimester; and 3.2 percent during the third trimester.
- The drugs prescribed included ACE inhibitors and angiotensin receptor blockers — both of which have been shown in studies to have harmful side effects during pregnancy.