The associations between cigarette smoking before and during pregnancy and maternal body size (pre-pregnancy weight status, end of pregnancy weight status, weight gain during pregnancy) and newborn size (birth weight, length, head circumference, arcomial circumference), as well as birth modus, were tested in 7803 single full-term births in Vienna. Nicotine consumption before and during pregnancy was found to be associated with smaller and lighter newborns, although maternal weight status and weight gain during pregnancy was signi.cantly higher in smokers. Furthermore, a higher incidence of Caesarean sections was found in smokers. A reduction in the number of daily smoked cigarettes was associated with a lower percentage of low weight newborns (<2500 g).