Antepartum fetal heart rate and uterine activity studies: I. Preliminary report of accelerations and the oxytocin challenge test.

A series of 344 antepartum fetal heart rate studies in 209 high-risk patients is described. The importance of evaluation of accelerations of the fetal heart rate as well as periodic decelerations associated with uterine activity is demonstrated. Our data suggest that the absence of accelerations of the fetal heart rate during the recording period may be associated with increased perinatal morbidity. Late decelerations may occur in the same recording session as accelerations of the fetal heart rate. The association of late decelerations of the fetal heart rate with no accelerations during the recording session is highly suggestive of increased perinatal morbidity. In high-risk patients, accelerations of the fetal heart rate and no late decelerations with uterine activity are a reassuring finding, with 91 per cent of patients showing no increased perinatal morbidity.