Oxidative stress and normal pregnancy

Abstract

Objective: To determine whether, in normal pregnancies, there is evidence of oxidative stress that is related to the lipid changes observed in pregnancy.

Design: Longitudinal study of healthy women having a normal pregnancy. Samples were obtained towards the end of each trimester and after 8 weeks postpartum.

Patients: Seventeen healthy women during a normal singleton pregnancy were compared with 12 healthy, non-pregnant women.

Measurements: Oxidative stress was determined by measuring total antioxidant capacity (TAC), uric acid and lipid hydroperoxides (LHP). Lipid status was evaluated by measuring total and high-density lipoprotein cholesterol, triglycerides and low-density lipoprotein (LDL) subfractions.

Results: Pregnancy was associated with decreased TAC and uric acid in the first trimester, which gradually increased during pregnancy, reaching normal values during the postpartum period. LHP significantly increased towards the end of pregnancy. The changes observed in LHP were significantly correlated with increases in LDL subfraction profile.

Conclusions: Late pregnancy was associated with the formation of susceptible, oxidisable particles (high LDL score) and an increase in oxidative damage. These biochemical changes may be relevant for the long-term cardiovascular health of women, especially those of high parity or those who are at high risk for cardiovascular disease (e.g. women with diabetes).