CKBB-enzyme activity in serum in neonates born after vaginal delivery and cesarean section.

Creatine kinaseBB has been analysed in blood from the umbilical cord and from venous blood within 24 hours after birth in infants without any signs of perinatal asphyxia. S-CKBB activity was found to be much higher than in adults and older children. 25% of the children born after normal vaginal delivery showed very high S-CKBB activities, higher than any of the children born by elective cesarean section. There were, however, no signs of neurological disturbances to be found in any of these children with high neonatal CKBB activities at follow-up after four years.