Nicotine Use and Effects On Children - 9987

Study shows that children of mothers smoking while pregnant has great effects during early adolescence

Mothers who use nicotine during pregancy shows effects on children such as performing more poorly on tests of general intelligence and on tasks requiring auditory memory than do children who were not exposed to cigarette smoke before birth, according to NIDA-supported researchers at Carleton University in Ottawa, Canada. Dr. Peter Fried and his colleagues, who have followed the development of children born to smoking mothers as part of the Ottawa Prenatal Prospective Study, previously reported poorer cognitive abilities in children of smokers when the children were ages 5 to 6 and 9 to 12. The results we see now that the children are 13- to 16-year-olds continue to suggest that exposure to cigarettes before birth has negative impact on general IQ and on auditory memory. And nicotine use effects children are dose-related: The deficits are more severe in children with mothers who heavily abuse nicotine or are considered heavy smokers.

The scientists administered a battery of tests to 145 13- to 16-year-olds (78 boys, 67 girls) whose mothers smoked heavily (more than a pack per day), lightly (less than a pack per day), or not at all during their pregnancies. The tests included measures of general achievement (reading and language skills), visual memory (identifying a missing number from a random sequence of numbers from 1 to 10), auditory memory (repeating tape-recorded sentences of increasing length and complexity), and general intelligence (IQ scores). In some tests there were no significant differences among the children. In tests of general intelligence and auditory memory, however, children born to smokers had lower scores than did children of nonsmokers, and children born to heavy smokers had poorer scores than children of light smokers. For example, in the general intelligence test, for which scores from 99 to 109 are considered "normal," children of nonsmokers had an average score of 113.4; of light smokers, 109.8; and of heavy smokers, 105.2.

In some areas of cognitive function, the gap in test results between exposed and unexposed children has narrowed as the children have grown, observes Dr. Fried. This improvement is most notable in tests that measure achievement rather than innate ability. For instance, although measured IQ remains lower for exposed children, their scores on reading and language skills are equivalent to those of unexposed children. "This comparative improvement in achievement is associated most strongly with the educational level of the parents. Achievement tests are in many ways a measure of formal learning acquired at home and in school. It appears that family and environmental factors that support learning can help moderate the negative effects seen in measures of ability," Dr. Fried explains.

"The improvements found in this most recent study of these children are encouraging," says Dr. Vincent Smeriglio, chair of NIDA\s Child and Adolescent Work Group. Nonetheless, the continued finding of poorer performance as the exposed children enter adolescence underscores the damage that appears to be done by nicotine use during pregnancyl, which can effect our children. These kids may be catching up in some ways, but they started out with a serious disadvantage.

Information released by the National Institute on Drug Abuse