A new study reveals that women who take epilepsy drug during pregnancy might be causing harm to their children much before they are born. The epilepsy drug can increase the risk of autism in children.

According to experts, the usefulness of the drug is defeated by the risk to the developing baby.

The results of the study were published in the journal Neurology. Research was conducted on 632 children from womb to birth and into childhood between 2000 and 2006. Nearly half the children were exposed to various epilepsy drugs in the womb, while the other half were not.

The mothers who were taking valproate alone for epilepsy were endangering their children by autism seven times more. The findings were based on results of the children who did not have any known family history of autism.

But with this study, "There's an inkling that there may be a specific kind of brain injury resulting from a chemical exposure in utero that causes autism -- that would be more of a surprise and more of a change."

Epileptic women have always faced a special challenge with pregnancy. Neurologists in the United States say that the study has raised issues for both parents in the epilepsy community and autism researchers.

"These findings are only preliminary. More research is needed in this area and into the more general area of autism itself," said Rebecca Bromley, a co-author of the study and an assistant psychologist at the Liverpool and Manchester Neurodevelopment Group at the University of Liverpool in England.