But girls who had prenatal exposure to similar amounts of cocaine were not more likely to suffer from the same problems, Virginia Delaney-Black, M.D., of Children's Hospital of Michigan and colleagues found. The study results are published in the Journal of Developmental and Behavioral Pediatrics.
While no specific cause of the gender-specific findings was identified, the researchers note that the study confirms animal studies that also suggest gender plays a role in the effects of cocaine exposure.
Delaney-Black and colleagues say human studies have been "inconsistent" on the question of whether prenatal cocaine exposure has gender-specific effects on children's development.
The study looked at 473 children in the Detroit area ages 6 to 7 whose mothers had received prenatal care and drug testing. About 200 of the children in the study were prenatally exposed to cocaine. Children were considered "persistently" exposed if they or their mothers tested positive for traces of cocaine in their urine at the time of birth.
To determine whether these children had a higher likelihood of behavioral and other cognitive problems, Delaney-Black and colleagues collected information on the children's behavior from their teachers.
After accounting for other factors like violence in the home or neighborhood, parents' income and marital status, boys who had been persistently exposed to cocaine in the womb had more behavioral problems and problems with abstract thinking and motor skills than those who had never been exposed to cocaine or those who had only some prenatal exposure to the drug.
The study was supported by the National Institute on Drug Abuse, the Helppie Institute for Urban Pediatric Health Research, Childrens' Research Center of Michigan and The Carman and Ann Adams Department of Pediatrics at Children's Hospital of Michigan.
By Becky Ham, science writer
Health Behavior News Service
FOR MORE INFORMATION
Health Behavior News Service: 202-387-2829 or www.hbns.org.
Interviews: Contact Virginia Delaney-Black at 313-745-0201.
Journal of Developmental and Behavioral Pediatrics: Contact Mary Sharkey at 212-595-7717.