Tobacco smoke and the chemicals produced have long been linked to problems and conditions with the fetus. The conditions range from low birth weight, prematurity and in some instances birth defects. Several studies have attempted to link tobacco smoke to autism spectrum disorder (ASD). ASD is a wide variety of conditions, including, Asperger Syndrome, Pervasive Development Disorder and Autistic Disorder. The Journal of Autism and Developmental Disorders recently published a population-based study researching the link between autism and prenatal exposure to tobacco smoke.

The study considered several factors that could potentially increase the link between autism and prenatal exposure to tobacco smoke. The main factor studied was environmental chemical exposure during pregnancy as well as during the early years after birth. Prenatal exposure to tobacco smoke was chosen due to studies throughout the years that have linked the chemicals in tobacco smoke to complications and behavioral disorders. The results are mixed when autism and maternal smoking have been studied in the past. The evidence has not been conclusive that there is a link between ASD and prenatal exposure to tobacco smoke.

Dr. Brian Lee, one of the study authors, collaborated with the Karolinska Institute in Sweden and concluded that prenatal exposure to tobacco smoke did not increase autism spectrum disorders. On the contrary, the research suggested that previous studies linked ASD to demographic and socio-economic factors such as occupation, education, and income.

Lee utilized data from 3,958 children with ASD as well as a control group of 38,983 non-ASD children born during the same timeframe. The children born with ASD were exposed to tobacco smoke at a rate of 19.8%, while the control group was exposed to maternal smoking at a rate of 18.4%. The research proved a link between prenatal exposure to tobacco smoke and ASD, but when socio-economic and demographic factors were included, the link quickly diminished.

Lee concluded that the link between prenatal exposure to tobacco smoke and ASD could be “crossed off the list of environmental factors” that potentially cause ASD. Although smoking is still considered unhealthy and causes additional health risks, prenatal exposure to tobacco smoke can potentially be ruled out as a cause for ASD in children.

Source: Brian K. Lee, Renee M. Gardner, Henrik Dal, Anna Svensson, Maria Rosaria Galanti, Dheeraj Rai, Christina Dalman, Cecilia Magnusson. Journal of Autism and Developmental Disorders. 12 January, 2012.