Circulating antioxidant profile of pregnant women with asthma

Background & aims: One of the most prevalent complications of pregnancy is asthma which is associated with an increased incidence of intrauterine growth restriction. The mechanisms that affect fetal development in pregnancies complicated by asthma are not clearly defined. Antioxidants are particularly important during pregnancy due to their protective role against a state of high oxidative stress as gestation progresses. The current study was designed to characterise the circulating profile of tocopherols and carotenoids in pregnant women with asthma to determine whether asthma severity and dietary intake were associated with an altered antioxidant profile.

Methods: Maternal dietary intake and plasma and erythrocyte concentrations of tocopherols and carotenoids were examined in women with (n = 84) and without asthma (n = 47) at 18, 30 and 36 weeks gestation. Tocopherol and carotenoid levels were related to fetal and birth outcomes.

Results: Pregnant women with moderate/severe asthma were found to have increased plasma concentrations of total carotenoids (P < 0.05), lutein (P < 0.05 and α-tocopherol (P < 0.02) late in gestation compared to those women with mild asthma and healthy pregnant controls. Moderate/severe asthmatics had higher erythrocyte α-tocopherol quinone levels early in gestation relative to the controls (P < 0.02) but this marker of oxidative stress decreased as gestation progressed. Tocopherols and carotenoids were positively associated with birth weight centile (P < 0.05).

Conclusion: These findings suggest that the maternal system adjusts antioxidant pathways in response to the presence of a high oxidative load induced by asthma during pregnancy in an attempt to ensure continued fetal growth in an adverse environment.