Does the baby gain weight during labour?

The present study was based on 6940 live singleton births without obvious congenital abnormalities delivered at 24-32 weeks. The birthweight of children born by Caesarean section was lower than that of those born vaginally. This applied whether the baby survived or died during the neonatal period; whether or not there was maternal hypertensive disease; and whether the delivery was at 24-28 or 29-32 weeks. Birthweight for gestational age was greater in those born by emergency Caesarean than those born by elective Caesarean section. After consideration of a number of potential confounding factors, these findings accord with the hypothesis that the baby might gain weight during labour.