Oxidative stress equilibrium during obstetric event in normal pregnancy.

OBJECTIVE: The aim of this study was to determine malondialdehyde (MDA) concentration as an oxidative stress marker and total antioxidant capacity (TAC) in pregnancy before and after perinatal event.

METHODS: This study was performed on 200 healthy full-term pregnant women admitted to pregnancy resolution in Maternal-Child Hospital of Durango, Mexico. Oxidative stress and TAC were assessed through detection of lipid peroxidation by quantitation of thiobarbituric acid-reactive substances (TBARS) and TAC through ferric reducing ability of the plasma (FRAP).

RESULTS: Our results showed increased levels of MDA after vaginal delivery (VD). TAC was also increased after obstetric event, but it did not differ between VD and caesarean section.

CONCLUSIONS: We demonstrated that MDA concentrations are increased two hours after obstetric event, and this increase correlates with VD. The TAC was increased as a compensatory mechanism during obstetric event. Another important finding is that women receiving analgesia administration in VD, as well as dexamethasone administration in caesarean section, experienced a protector effect that decreased MDA levels.