The treatment of paroxysmal supraventricular tachycardia (PSVT) in pregnancy is not unlike treatment for the general population. The physician should feel confident that the pharmacologic agents ordinarily used to treat this common problem in the general population are safe for both mother and fetus when administered under monitored conditions. In treating paroxysmal supraventricular tachycardia in pregnancy, when both vagal maneuvers and exhaustive medical therapy fail, synchronized, direct-current cardioversion is a safe and effective form of treatment.