Another Impact of Smoking During Pregnancy: Troubled Kids

March 8, 2007 — -- Smoking during pregnancy may have longer lasting effects on your child than you might think -- particularly on a child's long-term behavior.

Michigan State University researchers Dr. Joel Nigg and Dr. Naomi Breslau addressed these effects in a study published in this month's Journal of the American Academy of Child and Adolescent Psychiatry.

Nigg and Breslau followed just over 700 children from age 6 through age 17, randomly selected from two groups: those with normal birth weight and those with low birth weight (less than 5 lbs 8 oz).

Their main goal was to tease out the influences of low birth weight and maternal smoking -- singly and combined -- on the development of attention deficit hyperactivity disorder (ADHD), as well as two other specific behavioral disorders in children: Oppositional Defiant Disorder (ODD) and Conduct Disorder (CD).

Most people are familiar with ADHD, a syndrome that is first recognized in early childhood and is characterized by the core symptoms of hyperactivity, impulsivity and inattention.

Less well-known is ODD. Children with this condition frequently show loss of temper, are argumentative with adults, and refuse to obey rules, deliberate annoyance of others, as well as spitefulness and vindictiveness.

CD, another lesser known disorder, is thought to be a progression of ODD in most cases, includes more severe behaviors. These include aggression toward animals and people, destruction of property, excessive lying, theft, and serious violation of rules.

Using a variety of accepted methods to diagnose behavioral disorders, these researchers found that a mother's smoking during pregnancy influences the development of ODD and, later, CD.

The effect of smoking was independent of birth weight, as well as other maternal factors such as the mother's education, urban vs. suburban residence, and alcohol or drug abuse by the mother.

Taken together, these findings mean that a clearer line than ever can be drawn implicating smoking as a primary cause of these behavioral disorders.