OBJECTIVES: The author investigated the relationship between the environmental tobacco smoke exposure during mid-pregnancy and early childhood and neurobehavioral outcomes of preschool children and if there is any effect of the genetic polymorphism of glutathione S-transferase (GST) M1 and T1 on this relationship. METHODS: The participants were the pregnant women (week 24-28) who visited the obstetrics and gynecology department (between 2001 and 2004). They had been evaluated for their sociodemographic data including direct and environmental tobacco smoke exposure history and the urine specimen had been sampled for the measurement of cotinine. The offsprings' urine specimen and blood sampling had been done and the socioeconomic data including the environmental tobacco smoke exposure history was evaluated at age 3. The cotinine level of urine specimen was measured and GST polymorphism was analyzed. The offsprings completed Korean-Childhood Behavioral Check List (K-CBCL) at age 4-5. RESULTS: The environmental tobacco smoke exposure during mid-pregnancy based on urine cotinine level has a significant association with increased total score and externalizing problem score of K-CBCL (p<0.05). The environmental tobacco smoke exposure based on urine cotinine level at age 3 is associated increased total score, externalizing problem score and internalizing problem score of K-CBCL with no statistical significance. The environmental tobacco smoke exposure after controlling for tobacco smoke exposure during pregnancy, however, is significantly associated with the increased externalizing problem scores (p=0.04). The environmental tobacco smoke exposure is associated with increased total score, externalizing problem score and internalizing problem score of K-CBCL with GSTM1 null type or GSTT1 null type at age 3 although there was no statistical significance. CONCLUSION: The environmental tobacco smoking exposure during pregnancy and at early childhood is associated with childhood behavioral problems. The clinical implication of this study is that it is important to avoid the environmental tobacco smoke exposure during pregnancy and early childhood and to monitor the possible emergence of behavioral problems of children.
Child ; Child, Preschool ; Cotinine ; Female ; Glutathione ; Glutathione Transferase ; Gynecology ; Humans ; Obstetrics ; Organothiophosphorus Compounds ; Polymorphism, Genetic ; Pregnancy ; Pregnant Women ; Smoke ; Smoking ; Tobacco