Women who took folic acid supplements in early pregnancy almost halved the risk of having a child with autism. Beginning to take folic acid supplements later in pregnancy did not reduce the risk
This is shown in new findings from the ABC Study and Norwegian Mother and Child Cohort Study published in the Journal of The American Medical Association (JAMA).
Women who took folic acid supplements from four weeks before conception to eight weeks into pregnancy had a 40 per cent lower risk of giving birth to children with childhood autism (classic autism). Use of folic acid supplements midway through pregnancy (week 22) had no effect.
The findings only apply to a lower risk of childhood autism, the most severe form of autism. The results show no reduction in the risk of atypical or unspecific autism. The study also investigated the prevalence of Asperger syndrome, but the number of examined children was too low to give a reliable result.