[The effect of tobacco smoking during pregnancy on concentration of vitamin A and beta-carotene in matched-maternal cord pairs].

Tobacco smoking causes oxidant stress in pregnant women and may have a similar effect in fetus. Vitamin A and beta-carotene are natural factors protecting cells from damaging influence of free oxygen species.Therefore the aim of the study was to estimate the effect of tobacco smoking during pregnancy on concentration of vitamin A and beta-carotene in blood of mother and newborn. Healthy women in III trimester of pregnancy were divided into non-smoking (n = 40) and smoking group (n = 35) according to the concentration of cotinine in serum and urine. Level of carotenoids was measured by HPLC (high pressure liquid chromatography) method in plasma of matched-maternal cord pairs. We observed that, in smoking women group concentration of vitamin A was lower in plasma of mothers as well as in cord blood of newborn (p < 0.001) and amounted respectively only 80% and 70% of that observed in non-smoking mother and their child. In smoking group plasma level of beta-carotene was significantly lower (by 30%; p < 0.0001) as compared with non-smoking matched-maternal cord pairs. Plasma level of vitamin A was significantly correlated with concentration of pcarotene both in smoking and non-smoking pregnant women (r = 0.70, p < 0.001; r = 0.57, p < 0.001). The similar correlation was observed in umbilical cord blood in both groups (r = 0.81 and r = 0.82; p < 0.001). Reduced concentration of vitamin A and beta-carotene in matched-maternal cord pairs suggest that consumption of this antioxidant for neutralization of free radicals present in cigarette smoking is enhanced.