Interim results of a study being conducted by scientists at the University of Liverpool suggest that children aged three years and younger, who are born to women taking the anti-epileptic drug sodium valproate whilst pregnant, are likely to have an IQ of six to nine points lower than average.
The research, in collaboration with Emory University in the US and the Central Manchester University Hospitals NHS Foundation Trust, tested more than 300 three-year-olds in the UK and US, whose mothers took one of four anti-epilepsy drugs (AEDs) whilst pregnant. The preliminary findings suggest that children exposed to the drug sodium valproate had lower IQ results than children exposed to other AEDs, regardless of the mother's IQ. The results also took dosage, duration of pregnancy and mother's consumption of folic acid whilst pregnant, into account.
Professor of Clinical Neuropsychology at the University, Gus Baker, said "Our research looked at how exposure to sodium valproate and other AEDs in the womb affected children's everyday life - in particular their IQ, memory and language abilities from one to six years of age."
Around 5,000 women with epilepsy become pregnant every year in the UK and the majority of these, including those on AEDs, will experience uncomplicated pregnancies and births. Previous research conducted by the team has already shown that children exposed to AEDs such as sodium valproate in the womb are more likely to suffer birth defects characterised by heart malformations, dysmorphic features and minor limb deformities.