The significance of fetal cerebral blood flow analysis in the prediction of neonatal neurologic outcome was investigated on 87 fetuses at risk for chronic hypoxia. Blood flow velocity waveforms were recorded from the fetal internal carotid artery immediately before cesarean section; newborns underwent neurologic follow-up until discharged from the neonatal division. Neonatal outcome was considered abnormal in presence of a postasphyxial encephalopathy. Receiver operating characteristic curves were used to demonstrate the efficacy of fetal cerebral blood flow velocity waveform analysis as a predictor of neonatal outcome. A value of the pulsatility index from the internal carotid artery below the second standard deviation of our range of normality was found to be a powerful indicator of the development of neonatal neurologic abnormalities (Cohen's Kappa index = .58). These results were particularly evident in fetuses with a birthweight above 2500 g in which a specificity of 93.7%, a sensitivity of 75%, and an accuracy of 89.7% were achieved.