According to the Journal of Neurology Neurosurgery and Psychiatry, women who took the antiepileptic drug sodium valproate while pregnant are at significantly increased risk of having a child with autism and other neurodevelopmental disorders.  The authors followed 528 pregnant women who gave birth to children between 2000-2004.

Roughly half of the mothers had epilepsy and out of the 243 with epilepsy, 209 took antiepileptic drugs during their pregnancy.  The drugs taken were carbamazepine, valproate, lamotrigine was taken by some mothers, while others took a combination of these drugs and a few mothers took other ones altogether.  

Their children were asessed at the ages of one, three and six years old for physical and intellectual development.  Also maternal intake was conducted to discern whether they needed to consult specialists about their child's behavior, development, educational progress or health.  Of the 209, twelve had autism, three had ADHD and four had dyspraxia. 

Neurodevelopmental problems were significantly more common among children whose mothers had epilepsy; 7.46% compared with 1.87% of those whose mothers did not have the condition.  The mothers who had taken valproate alone or in combination with other drugs while pregnant were significantly more likely to have a child diagnosed with a neurodevelopmental condition than mothers who had taken other drugs to treat their condition.

About 1 in 10 children whose mothers had taken valproate during pregnancy had a neurodevelopmental problem as did 1 in 7 of those whose moms had taken valproate with other drugs.  Mothers who had epilepsy but did not take drugs for their condition, did not have children with a neurodevelopmental disorder.  Boys were three times more likely to have a disorder than girls.