Effects of maternal smoking upon neuropsychological development in early childhood: importance of taking account of social and environmental factors

Abstract
Data from a prospective study of 548 children followed from birth to 4 years of age were analysed to determine whether maternal smoking during and/or after pregnancy affects children's neuropsychological development. The differences in mean developmental test scores between children whose mothers smoked and those of mothers who did not smoke were slight, with subscale scores only 2.4 to 4.1% lower in children whose mothers smoked. These differences were not statistically significant after adjustment for socio-economic status, quality of home environment and mother's intelligence, suggesting that the social and environmental factors are major confounders of the association of exposure to maternal smoking and neuropsychological development in childhood. In order to gain a better understanding of this area, more precise measures of exposure to environmental tobacco smoke and comprehensive consideration of confounders will be required.