Objective: To determine there are differences in the production levels of oxygen free radical between mothers and neonates by the mode of delivery, we measured oxygen free radical concentrations in maternal vein and umbilical artery.
Methods: Forty-four women with singleton term pregnancies were prospectively recruited and classified into two groups: those who had a spontaneous uncomplicated vaginal delivery (VD group; n = 21), and those who had an elective cesarean delivery (CD group; n = 23). We determined maternal and fetal oxidative stress levels by measuring concentrations of derivatives of reactive oxygen metabolites (d-ROMs) in maternal vein before delivery and on postnatal day 5, and in umbilical artery at delivery. We also measured the pH, partial pressure of oxygen (PaO₂), partial pressure of carbon dioxide (PaCO₂) and base excess (BE) in umbilical artery blood collected at delivery.
Results: The concentrations of d-ROMs in maternal vein on postnatal day 5 were significantly decreased in the VD group, but were significantly increased in the CD group, compared to before delivery. The concentrations of d-ROMs in umbilical artery were significantly higher in the VD group than the CD group. Compared to the CD group, umbilical artery pH tended to be lower (p = 0.07), and BE significantly lower (p < 0.005), in the VD group. There were no significant differences in umbilical artery PaO₂ and PaCO₂ between the two groups.
Conclusion: Our findings indicate that those production levels of oxygen free radical in mothers are greater by CD than by VD, while those in neonates are greater by VD than by CD.