We recorded the electrical signals from bipolar electrodes placed on the abdomen of 7 adults and 10 newborn infants. Data were analyzed by visual inspection and by a wave analysis computer program with a fast Fourier transform. Waves of 3 cycles/min were recorded in adults, and similar 3 cycles/min waves were recorded in infants as well. The percentage of time of 3 cycles/min waves was lower in neonates (13.8% +/- 10.8%) than in adults (57.9% +/- 27.8%) (p < 0.01). Only an electrocardiogram superimposing the flat baseline was recorded in the remaining recording time. Spectral analysis confirmed the validity of the visual analysis, showing clear peaks at 0.05 Hz only when 3 cycles/min waves were visually present and motion artifact was absent. The electrode positions where percentage of time of 3 cycles/min waves was greatest were different for newborns and adults. There was no significant difference in the mean amplitude of the waves between groups. These facts indicate that the electrogastrogram of neonates is different from that of adults in terms of best electrode positions and percentage of time of 3 cycles/min waves.