Smoking during pregnancy and babbling abilities of the 8-month-old infant.

Animal experiments suggest that the fetal brain is sensitive to nicotine. Although much attention has been given to the relation between cigarette smoking during pregnancy and neurodevelopment in children, this remains controversial. Our study describes the relationship between maternal cigarette smoking during pregnancy and babbling abilities of the 8-month-old infant. In a longitudinal cohort, information was collected at the 16th week of gestation, at delivery and when the infant was about 8 months old. At this age babbling abilities of the infant were evaluated by a health visitor during a home visit. Singleton infants without any disability born at Aarhus University Hospital, Denmark, 1991-92 and still living in the Community of Aarhus at the age of 8 months were eligible (n = 2302). Complete follow-up was obtained for 1871 children (81.3%). A dose-response-like relationship between number of cigarettes smoked per day during pregnancy and babbling abilities was found after controlling for potential confounders. Smoking 10 or more cigarettes per day during pregnancy almost doubled the risk (odds ratio [OR] = 2.0, 95% confidence interval [CI] 1.1-3.6) of the infant being a non-babbler at the examination at 8 months. Among children who were breast fed for less than 4 months this risk was even higher (OR = 2.7, CI 1.3-5.8).