[Doppler ultrasound of the middle cerebral artery: pre-final normalization of cerebrovascular circulation?].

We report on the circulatory changes of a severely growth-retarded fetus at 26 weeks of gestation with intrauterine death after 6 days of observation and a birth weight of 480 g. On admission the fetus already showed signs of circulatory centralisation; furthermore, we found pulsation in the umbilical vein and diastolic reverse flow in the umbilical artery. During the days of observation this reverse flow increased and the compensatory phase of fetal circulatory centralisation was followed on the last day by a phase of circulatory decompensation with an apparently normal middle cerebral artery waveform, mimicking preterminal normalisation of fetal cerebral blood flow.