Maternal Cigarette Smoking and Congenital Heart Defects

Abstract

Congenital heart defects (CHDs) are of public health concern because they affect approximately 1% of newborns,1-3 are a leading cause of infant mortality,4 and often result in increased use and costs of health services among affected children, adolescents, and adults.5 In recent decades, epidemiologic research has made notable progress in the identification of modifiable risk factors for some CHDs (eg, congenital rubella infection, use of certain medications, and pregestational diabetes).6 For most CHDs, however, the causes remain unknown. In this issue of The Journal, Sullivan et al7 describe results of a population-based study in which they assessed the possible association of maternal periconceptional cigarette smoking and the occurrence of CHDs among live births by linking self-reports of cigarette smoking on birth certificates with records of children with CHD (ie, cases) identified from birth certificates and a statewide hospital discharge registry. The authors examined 19 specific CHD phenotypes and observed associations between maternal cigarette smoking during the first trimester of pregnancy and 3 phenotypes: pulmonary valve anomalies, pulmonary artery anomalies, and isolated secundum type of atrial septal defects. They also observed a suggestion of a doseresponse relationship between maternal cigarette smoking and the risk of CHDs examined as a group. These findings are of interest because they highlight: (1) methodologic issues common to studies of associations of maternal cigarette smoking, a prevalent and modifiable exposure, with specific CHD phenotypes in the offspring; (2) challenges in interpreting the nature of observed associations between maternal cigarette smoking and CHDs; and (3) opportunities for prevention and smoking cessation efforts among women of childbearing age.