Iron deficiency in newborns of mothers smoking cigarette during pregnancy

Iron deficiency during pregnancy affects about 50% of women and is one of the most widespread nutritional deficiencies in industrial as well as developing countries. Iron deficiency in pregnant women is assumed to be enhanced by cigarette smoking. The epidemiology studies conducted in the Institute of Mother and Child indicate that in Poland 25-35% of women smoke during pregnancy. Maternal smoking is associated, probably through a hypoxic effect on the fetus, with stimulation of fetal erythropoiesis and with increased fetal iron requirements. Recently as a central mediator of iron metabolism has emerge hepcidin a peptide hormone produced by the liver as prohepcidin. It is known that anemia and hypoxia suppress hepcidine mRNA expression. The effect of tobacco smoking on serum concentration of prohepcidin and some iron parameters in pregnant women and their newborns were studied using a commercial prohepcidin assay (DRG, Germany). Healthy matched-maternal cord pairs (n=60) were divided into nonsmoking and smoking group according to questionnaire declaration. In smoking group lower concentrations of prohepcidin in serum of mothers and in cord blood were obserwed. It amounted respectively only to 85% (p<0.01) and 70% (p<0.0001) of that found in non-smoking mothers and their children. In both studied groups concentrations of prohormone in serum of women correlated positively with that in cord blood (r=0.68; r=0.54; p<0.05). In smoking mothers total iron concentration was 20% lower than in nonsmoking ones. In cord blood of their children not only total iron but also ferritin and transferin concentrations were decreased by 20%, 30% and 13% respectively in comparison to the tobacco abstinent (p<0.05). Our results indicate that tobacco smoking during pregnancy affected prohepcidine levels in serum of mothers and of their newborns. Low concentrations of some iron markers in umbilical cord blood suggest that mother’s smoking could lead to subclinical iron deficiency in fetus.