Association of spontaneous fetal heart rate decelerations during antepartum nonstress testing and intrauterine growth retardation.

Two hundred one patients with high-risk pregnancy and 66 patients with term uncomplicated pregnancy underwent a nonstress test 7 days or less prior to delivery. The incidence of spontaneous fetal heart rate decelerations in the high-risk group was 5.5%. None of the fetuses in the normal group showed this finding. Among those infants presenting with spontaneous decelerations, there was an 18.2% mortality. Disturbances of intrauterine growth were found in 63.6% of cases. The possible metabolic mechanisms and clinical implications underlying this finding are discussed.