Women who smoke during pregnancy are nearly twice as likely to have children with attention-deficit/hyperactivity disorder (ADHD), a new study finds.
“This study serves to underline the fact that women who are pregnant should stop smoking,” said lead researcher Dr. Karen Markussen Linnet, a pediatrician at Aarhus University Hospital in Denmark. “We are not able to make a certain conclusion, but this study points out that there is an association between smoking and ADHD.”
Reporting in the August issue of Pediatrics, Linnet and her colleagues used extensive data available from the Danish government’s longitudinal registers on nearly 4,000 children born between 1991 and 1994. They compared the smoking habits of the mothers of 170 children who were later diagnosed with ADHD — or hyperkinetic disorder, as it’s called in Europe — with 3,765 mothers whose children were not hyperactive.
After controlling for low birth weight of babies, poor newborn health status, young maternal age and low socioeconomic status, smoking mothers were nearly twice as likely to have children with ADHD than mothers who didn’t smoke while pregnant. Fifty-nine percent of the mothers of ADHD children smoked during pregnancy, compared to 35 percent of the mothers whose children did not have the disorder.