The risk of intrauterine growth retardation (IUGR) and preterm delivery, in the group of 551 females from the area of Lódź, was related to the amount of cigarettes smoked per day. In subjects smoking more than 20 cigarettes, the risk of IUGR and preterm delivery was five times as high as in the nonsmoking females. The average weight of the newborns was found to be 510 g lower in the group of the most heavy smokers as compared with the nonsmoking subjects. The study has not provided any clear evidence for the pre-pregnancy smoking and the passive smoking as the risk factors for the pathologies under study.