Relationships Between Maternal Smoking,Placental Pathology,and Fetal Growth

Placental and feto-neonatal characteristics were compared between 199 smokers and 231 non-smokers. Controlling for such maternal confounders as maternal age, gestational age, race, socioeconomic status drug and/or ethanol abuse, and lack of prenatal care, maternal smoking was strongly related to decreased birth weight (mean difference 415 grams), length, head circumference, and elevated cord hematocrit, indicating early and late components of the growth-inhibiting effects of smoking. These relationships persisted when growth measures were adjusted for effects of placental weight, presence of placental infarction, or other specific placental lesions.