The influence of maternal smoking on maternal and newborn oxidant and antioxidant status

Maternal smoking has been suggested as a source of oxidant stress in pregnant women and in newborns exposed in utero. The aim of this study was to determine the influence of maternal smoking on oxidant status and antioxidant vitamins of mother-infant pairs.

Socioeconomic and diet characteristics were recorded from 20 smoker and 20 non-smoker pregnant women of 36 weeks' gestation. On the day of delivery, venous blood samples of the women and cord bloods were taken. On postpartum day 7, milk and infant urine samples were collected. Plasma and milk beta-carotene, retinol, alpha-tocopherol and cotinine levels, plasma malondialdehyde levels, and urine cotinine levels were measured.

Milk alpha-tocopherol levels of smoking mothers were lower than those of non-smoking mothers. In smokers, there were no correlations between maternal vitamin A intakes and milk levels of retinol, and between maternal plasma levels and milk levels of beta-carotene.

Maternal smoking may lead to decreased milk levels of vitamin E, as a result of making use of this antioxidant in order to limit lipid peroxidation, as well as may lead to a possible limitation on the transfer of lipophilic antioxidants including vitamin A from blood plasma to milk. Further investigations conducted in large populations will be needed to assess the effects of maternal smoking on the oxidant and antioxidant status of breast milk.