The nonstress test for the antepartum assessment of fetal reserve.

Seven hundred and twenty-two nonstress tests (NSTs) that were performed on a total of 471 patients were reviewed. The results of the study suggest that the NST is a simple, reliable test as a primary screening procedure in antepartum fetal heart rate (FHR) monitoring. The active and reactive tests were indeed reliable indicators of fetal well-being while the nonreactive test required an additional discriminatory evaluation. A tentative classification is suggested for those cases with FHR decelerations associated with fetal activity and uterine contractions.