Prevention of pediatric pulmonary problems: the importance of maternal smoking.

Although many factors are associated with lower respiratory illnesses in children, few can be identified as likely direct causal influences. Maternal smoking has been strongly associated with respiratory morbidity in early life. The relationship is consistent in different studies, and is dose-related. It is also resistant to attempts at statistical control for factors that might confound the association. The effect seems most marked from maternal smoking during pregnancy. Stopping young women taking up cigarette smoking is a priority preventive medical need.