Criminal links to prenatal smoking.

Violent crime rates rise sharply among men whose mothers smoked cigarettes during pregnancy and also experienced delivery complications, a new analysis finds.

The link appeared most striking for men into their mid-30s who repeatedly committed violent crimes, report psychologist Patricia A. Brennan of Emory University in Atlanta and her coworkers. No such association emerged between mothers' cigarette smoking and teenage criminal activity.

Brennan's group examined extensive data through 1994 on 4,169 Danish men born from September 1959 to December 1961 in Copenhagen. During the third trimester of pregnancy, their mothers had reported the number of cigarettes smoked daily. The researchers statistically accounted for social, familial, and maternal factors thought to increase criminal behavior.

Maternal cigarette smoking may damage the fetal brain in ways that later promote criminality, the researchers theorize in the March Archives of General Psychiatry. However, it's still unclear whether a mother's smoking during pregnancy directly affects her child's propensity for lawbreaking, cautions psychologist David M. Fergusson of Christchurch (New Zealand) School of Medicine in an accompanying comment.