Objective: To evaluate blood pressure control during the immediate postpartum in hypertensive women who had used methyldopa during pregnancy, comparing continuation of that drug with switching it for captopril. Methods: A single-blind, randomized clinical trial involving 180 postpartum women with arterial hypertension who had previously used methyldopa during pregnancy at a minimum dose of 750 mg/day for at least one week prior to delivery. Following delivery, the patients were randomized either to continue with methyldopa (minimum dose 250 mg, three times a day) (methyldopa group, n=90) or to switch to captopril (at an initial dose of 25 mg, three times a day) (captopril group, n=90). Logistic regression will be used to compare the groups regarding the potential to maintain blood pressure below 140/90 mmHg at over 50% of measurements postpartum.