POSTNATAL ADAPTATION OF BRAIN-FUNCTION IN FULL-TERM NEONATES AS ASSESSED BY EEG SLEEP ANALYSES

Differences in electroencephalographic (EEG) sleep between preterm and full-term neonatal cohorts at matched postconceptional ages have been previously presented by our study group. These differences may have occurred, however, because of postnatal brain adaptation of the full-term infant after a more recent delivery. EEG sleep analyses, therefore, were performed on only the full-term cohort to determine if EEG sleep measures changed over the first three days after birth, which might account for the differences with the preterm group. Twelve fullterm infants studied on the first day of life were compared with 17 full-term infants who were studied on days of life 2 and 3. Using multivariate analysis of variance (MANOVA), comparisons were performed among 13 EEG sleep measures. No EEG sleep differences were seen between full-term children born by Cesarean section versus those born by vaginal presentation. No statistical differences were noted between day 1 compared to days 2 and 3 with respect to 10 measures concerning sleep architecture, phasic, continuity, spectral EEG, and autonomic features. In three EEG sleep measures, changes occurred between days 1 and 2-3, but two of the three measures were in a direction that strengthen our claim that differences exist between preterm and full-term cohorts: more body movements and lower percentages of quiet sleep were noted for full-term infants on days 2-3. EEG sleep differences between preterm and full-term infants at matched postconceptional term ages are more likely to be due to conditions associated with prematurity rather than postnatal brain adaptation in the full-term group who experienced a more recent delivery.