Which class of antihypertensive drugs is contraindicated during pregnancy?

ACE inhibitors are contraindicated during pregnancy due to their potential to cause significant fetal harm. These medications, which include drugs like enalapril, lisinopril, and ramipril, are known to be teratogenic, especially during the second and third trimesters. They can lead to serious complications such as fetal renal impairment, oligohydramnios (low amniotic fluid), pulmonary hypoplasia (underdeveloped lungs), and ultimately may result in stillbirth or neonatal death.

The impact of ACE inhibitors on the developing fetus is primarily due to their mechanism of action, which inhibits the renin-angiotensin-aldosterone system. This system is crucial for maintaining blood pressure and normal fluid balance; disrupting it during critical periods of fetal development can lead to adverse outcomes. Therefore, it is essential to avoid ACE inhibitors in pregnant patients and seek safer alternatives that provide effective blood pressure control without posing risks to the developing fetus.

Medications such as methyldopa, labetalol, and nifedipine are generally considered safe during pregnancy and are often prescribed to manage hypertension in pregnant patients.