Flow velocity waveforms in uterine and umbilical arteries during the angiotensin II sensitivity test.

The angiotensin II sensitivity test has been used to predict the development of hypertension during pregnancy. We investigated the systolic/diastolic ratios of flow velocity waveforms in the uterine and umbilical arteries by means of a color Doppler system in 15 healthy women at 24 to 26 weeks' gestation. A significant increase (p less than 0.001) was observed in the systolic/diastolic ratio in the uterine artery, which was unaffected by the location of the placenta. In five women a differential effect of angiotensin II on the systemic diastolic blood pressure and on the systolic/diastolic was observed: the uterine circulation appeared to have a slower response and a faster recovery than the diastolic blood pressure. No changes in the systolic/diastolic ratio in the umbilical artery were observed.