But a recent study out of Tennessee indicates that ACE inhibitors should not be used even in the first trimester, due to a higher incidence of congenital abnormalities in the fetus during this stage as well, including retarded growth and kidney failure of the fetus.
The Tennessee study involved 29,500 infants born over a 15-year period. Compared to infants born to mothers who took no anti-hypertensive medications, major congenital abnormalities were identified 2.7 times more often when newborns were exposed to an ACE inhibitor in the first trimester of pregnancy.
Especially common were cardiovascular malformations and abnormalities of the central nervous system. No increased risk was observed from exposure to other types of anti-hypertensive medications during the first trimester.
"Exposure to ACE inhibitors during the first trimester cannot be considered safe and should be avoided," the study's authors concluded. However, the Food and Drug Administration does not plan to require changes in the prescribing information for ACE inhibitors until it evaluates the new data further.
What should you do if you are one of the millions of American women being treated for high blood pressure and you become pregnant? Quite frankly, there is little information on the safety of the other anti-hypertensive drugs during pregnancy, since asking pregnant women to take these drugs to see if they cause birth defects would be unethical.
In my view, it would be prudent to avoid ACE inhibitors completely when attempting to become pregnant and during pregnancy. Yet because it is also critical to control blood pressure during pregnancy, I would recommend instead taking one of the other anti-hypertensive drugs that were not associated with the birth defects found in the Tennessee study.
