Epidemiological studies have reported associations between a range of cardiovascular risk factors such as smoking and intima-media thickness (IMT). Some reports indicate that the maternal tobacco smoking causes disturbances of the endocrine status of the foetus. There are several potential mechanisms by which insulin-like growth factor I (IGF-I) could modify atherosclerotic processes either locally or in a systemic manner. The aim of this study was to investigate the influence of maternal smoking on neonatal aortic IMT (aIMT), serum IGF-I and IGF-binding protein-3 (IGFBP-3) levels. Aortic intima-media thickness was measured in 28 neonates whose mothers smoked during the pregnancy and 28 control neonates. Mean and weight-adjusted aIMT were significantly greater in the neonates whose mothers smoked (0.455 +/- 0.009 mm and 0.151 +/- 0.005 mm/kg, respectively) than in controls (0.403 +/- 0.029 mm and 0.118 +/- 0.014 mm/kg, respectively). Birth-weight of newborns whose mothers smoked was less than that of the controls. The decreases in serum IGF-I and IGFBP-3 observed in the infants whose mothers smoked were non-significant. Mean aIMT was negatively associated with birth-weight and IGF-I level. In conclusion, neonates whose mothers smoked have significantly increased aIMT. It might play a role in the pathogenesis of atherosclerosis in adult life.