Effects of methyldopa on uteroplacental and fetal hemodynamics in pregnancy-induced hypertension.

Objective: Our purpose was to study the effect of methyldopa on uteroplacental and fetal hemodynamics in women with pregnancy-induced hypertension.

Study Design: A prospective study of Doppler ultrasonographic blood flow data before and after 1 week of methyldopa treatment was conducted at the Department of Obstetrics and Gynecology, National University Hospital, Singapore, in 20 women (mean 35 weeks' gestation) with pregnancy-induced hypertension. The main outcome measures were maternal blood pressure, maternal and fetal heart rate, and blood velocity waveforms characterized by the pulsatility index in the fetal ascending aorta, middle cerebral artery, umbilical artery, and maternal uterine and arcuate arteries. Statistical evaluation was performed with t tests for paired observations.

Results: Maternal mean arterial blood pressure was reduced 9.7 mm Hg (95% confidence interval -13.8 to -5.6), and mean heart rate decreased 6.3 beats/min (95% confidence interval -11.1 to -1.4). Mean pulsatility index in the uterine (0.93 to 0.92) and arcuate arteries (0.61 to 0.73) were unchanged after treatment. Fetal hemodynamic changes before and after treatment were not significant. Fetal and neonatal outcome was uneventful.

Conclusion: Short-term treatment with methyldopa in the last trimester in women with pregnancy-induced hypertension reduced maternal blood pressure and heart rate but had no adverse effects on uteroplacental and fetal hemodynamics.