Antioxidant levels in the cord blood of term fetus

The aim of this study was to compare the differences in the total antioxidant levels in the cord blood after a normal vaginal delivery and after an elective caesarean section. This was a prospective study approved by the Wirral Hospital ethical research committee. The study was carried out in a district general hospital. We investigated 96 healthy pregnant women who had normal antenatal period with singleton pregnancies between 37 and 42 completed weeks of gestation. Sixty-five women had a spontaneous normal vaginal delivery and 31 underwent elective caesarean section. Umbilical cord blood was obtained immediately after delivery. Antioxidants such as glutathione peroxidase (GPX) and superoxide dismutase (SOD) were measured and compared between the normal vaginal delivery and elective ceasarean sections. The mean values for GPx in umbilical cord arterial blood (95; 86-103, n=74) was found to be significantly higher (P=0.0133) than that found in umbilical cord venous blood (84; 80-88, n=95). The arterial SOD values were found to be significantly higher (P=0.0337) in infants who had been delivered by caesarean section (1188; 1065-1311, n=22) than by vaginal delivery (1021;958-1083, n=39). The differences in the levels of GPX between the arterial and venous systems is not well documented but may be due to differences in the level of selenium, hydroperoxides or glutathione. In addition, why infants delivered by ceasarian section have a higher level of arterial SOD than those delivered by vaginal delivery remains unclear, but it may be a reflection of a relatively low level in infants subjected to the stress of labour.