Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers in women of childbearing age: risks versus benefits.

Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) are effective and widely used antihypertensive drugs. Exposure to these agents is known to be harmful to the fetus in the second and third trimesters of pregnancy. Concerns have also been raised about the risk of congenital malformations if ACEIs or ARBs are taken during the first trimester of pregnancy. The evidence to date, however, is conflicting and observed malformations may be due to confounders such as undiagnosed diabetes or maternal obesity, other antihypertensive medications or the hypertension itself. Nonetheless, in women who become pregnant while taking an ACEI or ARB, the drug should be stopped as soon as possible. In women with chronic kidney disease and proteinuria, it may be appropriate to continue taking an ACEI or ARB until the pregnancy is confirmed because of the significant benefit to their kidney function and the lower fertility rate in these patients.