Newborns of smokers had a lower weight, a smaller head circumference, and were shorter than newborns of smokers and ex-smokers, who stopped smoking early in pregnancy. The activity and concentration of the enzyme which produces the vasodilator nitric oxide were 36% and 47% lower, respectively, in endothelial cells of the umbilical vein from smokers compared with that from nonsmokers and ex-smokers. The findings suggest that smoking reduces nitric oxide production in the foetal vascular bed, contributing to retarded foetal growth caused by the reduction of vasodilatory capacity.
Udgivelsesdato: 2009-Jun