Children born to mothers with epilepsy who took the anti-seizure medication valproate during pregnancy have an increased risk of developmental delay and cognitive impairment, according to results of a new study.

Dr. N. Adab, of The Walton Center for Neurology and Neurosurgery, Liverpool, UK, and colleagues studied 249 children between the ages of 6 months and 16 years born to mothers with epilepsy. Forty-one children were exposed during their mother’s pregnancy to sodium valproate, 52 to carbamazepine, 21 to phenytoin, 49 to multiple anti-seizure medications, and 80 were unexposed.

The researchers used structured interviews, hospital records, clinical examinations, and psychometric tests to assess the children’s degree of exposure to these drugs and their IQs. Photographs were used to score children with abnormally shaped facial features.

Children in the valproate group had significantly lower average verbal IQ scores compared with children who were not exposed as well as with children in the other single-drug groups, the researchers report in the Journal of Neurology, Neurosurgery, and Psychiatry.

Also, 44 percent of children exposed to valproate had moderately to severely abnormal features, compared with only two percent of unexposed children.

“Our data demand that epilepsy services deliver adequate information and counseling about drug treatment during childbearing years,” Adab’s group concludes. “This needs to be offered before pregnancy and updated regularly.”

SOURCE: Journal of Neurology, Neurosurgery, and Psychiatry; November 2004.