A study released today in Neurology reports that mothers treated with valproate during pregnancy were seven times more likely than untreated mothers to have a child who developed autism. The study, conducted by the Liverpool and Manchester Neurodevelopment Group, suggests there is a potentially increased risk for autism in children exposed prenatally to valproate, a drug used to treat epilepsy, bipolar disorder, migraine headaches, depression, and schizophrenia.

This study followed more than 600 children, approximately half of which were exposed to an anti-epileptic drug before birth. Nine children in the study went on to develop autism, seven of which were exposed to antiepileptic drugs, and five of which were exposed specifically to valproate.

Valproic acid treatment has commonly been used as an animal model for autism, yet this is the first human study indicating a significantly increased risk for autism in children exposed prenatally to the drug.  Valproate is a Class D pregnancy drug, meaning that there are human studies suggesting that prenatal exposure can increase the risk of birth defects. Women who are pregnant are generally advised to avoid this Class D drug, however, in some cases the inherent benefits of treatment may outweigh the potential risks.

This study could spark a public panic, especially in women who are or were previously treated with valproate for epilepsy, headaches, or other ailments. But what should these women plan to do after hearing such worrisome news?

Dr. Gus Baker of the University of Liverpool warns that “more research needs to be done since these are early findings. However, women who take valproate while pregnant should be informed of the possible risks of autism and are encouraged to discuss them with their doctor. Those who are taking valproate should not stop their treatment without speaking to their doctor first.”