Parental smoking during pregnancy and head shape and size in school children

Abstract

Background: Maternal smoking during pregnancy has been recognised as a detrimental factor associated with adverse perinatal outcomes; however, to date there is a dearth of information on how it affects post-natal head growth and shape.Aim: To assess the relationship between parental smoking exposure during pregnancy and head dimensions and shape at age 7–10 years in boys and girls.Methods: Body height and head length, breadth and circumference were measured. Birth weight and gestational age were obtained from the children’s medical record books. Parental smoking habits during pregnancy and maternal educational attainment were obtained by a questionnaire. The relationship between exposure to parental smoking during pregnancy and head dimensions was evaluated using analysis of covariance implemented in the Generalized Linear Model, separately for each sex.Results: Maternal and parental smoking during pregnancy significantly altered head shape in boys by affecting head length, while neither head breadth nor circumference were affected. This phenomenon was not observed in girls.Conclusion: Smoking-induced chronic hypoxic effects on the growing foetus, indicated that both active and passive smoking during pregnancy seems to have persistent negative effects on children, going beyond foetal development and pre-natal growth restrictions.