Long-term consequences of maternal smoking and developmental chronic nicotine exposure

Every year, a large number of children are exposed to smoking during pregnancy which increases the risk of decreased birth weight, fetal morbidity and behavioral abnormalities. Therefore, nicotine replacement therapy (NRT) is often considered as a treatment option. Despite a large number of epidemiological studies, there are conflicting reports about the long-term consequences of maternal smoking on cognitive function, attention deficit hyperactivity disorder (ADHD) and other behavioral abnormalities. Animal studies are also often contradicting with respect to the effects of developmental nicotine, the psychoactive ingredient in tobacco. After a critical review of the literature, it appears that 1) maternal smoking causes low birth weight and nicotine, seems play a significant role in reducing body weight; 2) maternal smoking and developmental nicotine exposure have only minor effects on cognitive functions in children or animals, respectively; 3) maternal smoking is a risk factor for ADHD, but a causal link between nicotine and hyperactivity is not well established; 4) developmental nicotine increases anxiety-like behavior in animals but it remains to be seen if maternal smoking or NRT, would have similar long-term effects in children. Future studies should address if nicotine is involved in the increased risk to develop ADHD and how developmental nicotine leads to increased anxiety.