BACKGROUND: Maternal smoking during pregnancy is known to be associated with perinatal complications such as preterm delivery, low birth weight, and sudden infant death syndrome. OBJECTIVE: The purpose of this study was to evaluate the influence of smoking during pregnancy on the risk of postnatal infections in preterm neonates. METHOD: We examined 80 preterm infants (gestational age 24-36 weeks), of whom 40% had been exposed to tobacco smoking during pregnancy. RESULTS: Infections occurred in 31 infants. Gestational age and maternal smoking had a significant effect on the occurrence of infections (p < 0.001 and p = 0.015, respectively). An increase in maternal tobacco consumption by 10 cigarettes/day showed an odds ratio of 2.7 (95% confidence interval 1.1-6.4) for occurrence of infections. CONCLUSIONS: A significant association between maternal use of tobacco and the occurrence of infections in preterm neonates was found. Thus, campaigns about the damaging effects of tobacco are still warranted. (c) 2008 S. Karger AG, Basel