A prospective study of continual heart rate monitoring is made in 57 normal newborn infants in the first two hours after birth. They were all divided into three groups according to their type of delivery. We have estimated the coefficient of variation, whose value quantifies the heart rate variability, obtained by continual monitoring. It was significantly lower (p less than 0.05) in newborns whose mothers had received anaesthesia during labour than in infants born by non-induced vaginal delivery. These results support the sensitivity of this method in order to assess neonatal cardiac readaptation.