Smoking during pregnancy is associated with pre- and postnatal growth retardation and increased risks of placental mortality, morbidity, and behavioral anomalies. The most likely explanation for these effects is that smoking causes fetal hypoxia resulting in interference with regulating state mechanisms and attenuation of cellular growth. In addition, smoking also increases the incidence of various complications of pregnancy which in turn compromises optimal development of the growing fetus.
Abel, Ernest L.
"Smoking During Pregnancy: A Review of Effects on Growth and Development of Offspring,"
4, Article 3.
Available at: https://digitalcommons.wayne.edu/humbiol/vol52/iss4/3