Determinants of umbilical cord arterial 8-iso-prostaglandin F-2 alpha concentrations

Objective To determine the concentration of 8-isoPGF(2 alpha) in cord blood as a measure of oxidative stress during labour, and to compare them with o ther established parameters of in vivo lipid peroxidation and with the acid -base status of the newborn. Method Umbilical cord arterial and venous blood samples were collected from 81 singleton term deliveries for determination of 8-isoPGF(2 alpha), malon dialdehyde and organic hydroperoxides. In addition, metabolites derived fro m the oxidative metabolism of purines during hypoxia-reoxygenation and rout ine cord blood of oxygen saturation, pH, pO(2), pCO(2), HCO3 and base exces s were measured. Results Arterial concentrations of 8-isoPGF(2 alpha) were significantly hig her in cases with fetal distress, tight nuchal cord (P < 0.001), the umbili cal coiling index, and male sex (P < 0.05) (R-2 = 0.48). No correlation was found with any parameter of acid-base status. In arterial and venous blood the concentrations of organic hydroperoxides and hypoxanthine significantl y correlated with the fetal nuchal cord (P < 0.001) (R-2 = 0.26 and 0.6, re spectively). Conclusion Our findings indicate that 8-isoPGF(2 alpha) in cord arterial bl ood is a suitable parameter to quantify a possible oxidative stress in the fetus during labour. Measurements of the F-2-isoprostane concentrations in cord blood at labour provide a clinically useful method to assess the perin atal outcome.