Role of oxidative stress and antioxidant supplementation in pregnancy disorders

Abstract

Oxidative stress is widely implicated in failed reproductive performance, including infertility, miscarriage, diabetes-related congenital malformations,andpreeclampsia. Maternal obesity is a strong risk factor for preeclampsia, and in a recent studyweobserved oxidative stress in the oocytes of obese animals before pregnancy as well as in earlystage embryos. This adds to the growing evidence that investigators need to focus more on the preconceptual period in efforts to prevent pregnancy disorders, including those related to oxidative stress. Our research has also focused on the role of free radicals and antioxidant capacity in preeclampsia. By measuring markers of lipid peroxidation and antioxidant capacity, we obtained unequivocal evidence for oxidative stress in this disorder. Partial failure of the process of placentation has been implicated, and recent findings suggest that ischemiareperfusion in the placenta may contribute to oxidative stress in trophoblasts. Endoplasmic reticulum stress in the placenta may also play a role. Randomized controlled trials have been conducted by ourgroupas well as others to determinewhether early supplementation with vitamins C and E in women at risk of preeclampsia is beneficial, but these trials have shown no evidence that these supplements can prevent preeclampsia. Whether this indicates that an inappropriate antioxidant strategy was used or supplementation was administered too late in gestation to be beneficial is not known. Other potential approaches for preventing preeclampsia through amelioration of oxidative stress include the use of supplements in the preconceptual period, selenium supplements, antiperoxynitrite strategies, and statins. © 2011 American Society for Nutrition.