Changes in maternal lipid peroxidation levels and antioxidant enzymatic activities before and after delivery.

OBJECTIVE Our goal was to characterize the changes in maternal lipid peroxidation levels and antioxidant enzymatic activities before and after delivery. METHODS Predelivery and 1, 24, and 48 hours post-partum plasma concentrations of malondialdehyde, erythrocyte enzyme superoxide dismutase, glutathione peroxidase and catalase were measured in uncomplicated pregnancies. RESULTS Malondialdehyde levels increased slightly from predelivery to 24 hours post-partum and then decreased significantly at 48 hours post-partum. At one hour post-partum superoxide dismutase and catalase levels increased significantly to about 125% and 170% of predelivery levels, respectively. Thereafter, these values decreased significantly from one hour to 48 hours post-partum. The relative changes in superoxide dismutase and catalase levels at one hour post-partum compared to predelivery values correlated significantly with the duration of labor. CONCLUSION The results suggest that the uncontrolled lipid peroxidation caused by reactive oxygen species, which are produced in consequence of tissue reoxygenation, may occur during labor and that prolonged labor, may cause maternal oxidative stress.