Pregnant women’s exposure to second-hand smoke linked
to conduct disorder, ADHD in their children

The children of women exposed to second-hand smoke during pregnancy may be at elevated risk for conduct disorder and attention deficit hyperactivity disorder (ADHD), according to a recent study.

Lisa Gatzke-Kopp and Theodore Beauchaine enrolled 133 mothers and their children in a study of the effects of prenatal exposure to nicotine. All of the children, who ranged in age from 7 to 15, had emotional or behavioral disorders. Several studies link cigarette smoking by pregnant women to behavior problems in their children (see related articles, Crime Times, 2006, Vol. 12, No. 4, Page 7, Crime Times, 2006, Vol. 12, No. 3, Page 3, and Crime Times, 2005, Vol. 11, No. 4, Page 3), but it’s not clear whether the connection stems from exposure to nicotine or from genetic influences. (Genetics could play a role if the mothers and their children share genes that influence both smoking and behavior problems.) To help clarify this issue, Gatzke-Kopp and Beauchaine studied three groups of women: non-smokers, smokers, and women who did not smoke during pregnancy but were exposed to significant amounts of cigarette smoke at home or at work.

The researchers report that children of smokers and mothers exposed to second-hand smoke had more severe symptoms of conduct disorder and ADHD than children of non-smokers—a finding that remained true when the researchers controlled for a wide range of variables. The increase in the risk for both CD and ADHD suggests, Gatzke-Kopp and Beauchaine say, that prenatal nicotine exposure is associated with a general vulnerability to impulsive behavior. This effect, they say, may stem from nicotine’s effects on dopamine cells that play a part in the brain’s reward system.

The researchers note that while many studies link prenatal nicotine exposure to “acting-out” behaviors, this is the first study to link second-hand smoke to these behaviors. They say the results, while preliminary, “support an environmental programming effect of nicotine and as such have important implications for public policies regarding healthy work environments for women of child bearing age, such as initiatives to eliminate indoor smoking in public settings.”