There has been a scientific study carried out in Denmark.  It looked at 650,000 children born between 1996 and 2006. The study found that the children’s risk of having any type of autism spectrum disorder was increased, when certain mothers took valproate during pregnancy.

There is already a known risk with taking sodium valproate during pregnancy. It increases the risk of children being born with birth defects and thinking problems. The new research also shows that valproate significantly increases the risk of having a child with autism or an autism spectrum disorder.

Autism is a lifelong developmental disability that affects how a person communicates with, and relates to, other people and the world around them.

It is a spectrum condition, which means that, while all people with autism share certain areas of difficulty, their condition will affect them in different ways. Asperger syndrome is a form of autism.

“The absolute risk of being diagnosed with an autism spectrum disorder was 4.4 per cent in children exposed to valproate. This is compared to 1.5 per cent in children not exposed. The absolute risk of being diagnosed with childhood autism was 2.5 per cent in children exposed to valproate. This is compared to 0.5 per cent in children not exposed to valproate,” said the author of the study, Jakob Christensen. The author is a consultant neurologist at Aarhus University Hospital in Aarhus, Denmark.

The study was published in the Journal of the American Medical Association.

Nicole Crosby-McKenna, Epilepsy Action’s senior policy and campaigns officer said: “It is vital that women and girls of child bearing potential taking any epilepsy medicine have access to specialist information and advice. This should cover contraception, conception and pregnancy.

“For some women, sodium valproate is the safest drug for them to take in pregnancy. This is because it is the only medicine that effectively controls their epilepsy. More research is needed to discover the best way to treat these women before and during pregnancy.

“Another researcher in this area raised an interesting question - do these children have true autism or is it actually foetal valproate syndrome? Is it a case that some of the common features of autistic spectrum disorder are also common features of foetal valproate syndrome?

“There is an urgent need for continuing studies in this area. We need to better understand the potential effects of exposure to maternal sodium valproate. This includes how to minimise these risks if possible, or identify the families at a higher risk of having a baby with foetal valproate syndrome. Research is also needed to highlight best practice care and interventions to use in children and adults with foetal valproate syndrome.”

Epilepsy Action does not advise women to stop taking sodium valproate unless their doctor advises them to do so.