Which antihypertensive class is contraindicated in pregnancy due to fetal risk, and what are preferred alternatives?

• A. Beta-blockers; alternatives: calcium channel blockers
• B. Thiazide diuretics; alternatives: ACE inhibitors
• C. ACE inhibitors/ARBs; alternatives: labetalol, methyldopa, hydralazine
• D. Calcium channel blockers; alternatives: diuretics

Answer: (C)

Antihypertensive therapy in pregnancy must avoid drugs that pose fetal risk. ACE inhibitors and ARBs disrupt the renin–angiotensin system crucial for fetal kidney development, and exposure—especially in the second and third trimesters—can cause fetal renal failure, oligohydramnios, skull hypoplasia, pulmonary underdevelopment, and even fetal death. For this reason, these drug classes are contraindicated during pregnancy. The preferred alternatives with solid safety data in pregnancy are methyldopa, labetalol, and hydralazine. Methyldopa has a long history of safe use for blood pressure control in pregnant patients. Labetalol provides effective BP management with a favorable fetal safety profile. Hydralazine is useful, particularly when rapid BP reduction is needed or for sustained control in some cases. (Calcium channel blockers like nifedipine can also be used in pregnancy, but among the listed options, the established first-line alternatives are methyldopa, labetalol, and hydralazine.)