We report a trial of the technical feasibility of monitoring the state of the fetal brain during labour using the Cerebral Function Monitor (CFM). This device was developed for long-term monitoring of the electroencephalogram (EEG). A tripolar scalp electrode allows removal of the fetal electrocardiograph (ECG) from the fetal EEG. Technically satisfactory recordings were obtained from 15 fetuses during labour for periods of up to 6 1/2 hours before delivery. There were alterations of CFM trace with fetal distress and also during general anesthesia for Caesarean section.