A

ACE inhibitors such as enalapril are teratogenic—late-pregnancy exposure is linked to fetal renal dysgenesis, oligohydramnios, pulmonary hypoplasia and neonatal anuric renal failure; therefore they are formally contraindicated throughout pregnancy [Hanssens, 1991, PMID 2047053]. In contrast, amlodipine and certain β-blockers (e.g., labetalol) are considered acceptable when indicated, and propylthiouracil is the preferred antithyroid agent in the first trimester.