Clinical evaluation of a "short" supine pressor test for pregnancy-induced hypertension.

A modified supine pressor test was performed on 304 apparently normal primigravidas between 28 and 32 weeks' gestation. The blood pressure was measured with the patient first in lateral position and within 2 minutes thereafter in the supine position. Of those patients showing an increase of at least 20 mmHg in the diastolic blood pressure while in the supine position, 13 of 76 (17%) developed pregnancy-induced hypertension. Of those patients without an increase of at least 20 mmHg in the diastolic blood pressure, 33 of 228 (14%) became hypertensive. The results of this study do not substantiate the use of the "short" supine pressor test as an accurate predictor of pregnancy-induced hypertension.