Hematological parameters and cobalamin status in infants born to smoking mothers.

Hematological parameters, serum cobalamin and folate levels, and the concentrations of the functional markers plasma methylmalonic acid and total homocysteine were determined in 173 newborns and 46 infants at 6 weeks to see whether maternal smoking influences the hematological parameters and the vitamin status of the newborn. At birth, there was a strong inverse correlation between the number of cigarettes smoked per day during pregnancy and red blood cell count (r = -0.56, p = 0.001) and hemoglobin level (r = -0.52, p = 0.003) in the newborns. Neonates born to smoking mothers had lower red blood cell counts and lower hemoglobin and serum cobalamin levels as compared with infants born to nonsmoking mothers. At 6 weeks, maternal smoking significantly predicted the methylmalonic acid and total homocysteine levels, suggesting an influence from smoking on the cobalamin function in these infants.