Smoking has a direct effect on the growth of the fetus.
The more the mother smokes during pregnancy, the lower the weight of the newborn infant. Such babies are more likely to be stillborn, to need intensive care in hospital or to die in infancy. Smoking can decrease the quantity of breast milk, can change its quality and may lead to early weaning. The more a pregnant woman smokes, the greater the risks. The Health Consequences of Smoking for Women.