Autism and Folic Acid in Pregnancy

William T. Basco, Jr., MD, MS


May 07, 2013

In This Article


Surén and colleagues acknowledge that their study was not adequately powered to detect differences in the frequency of diagnosis of Asperger syndrome or PDD-NOS, perhaps resulting in the lack of statistical significance with respect to these subgroups. Some strengths of the study are the large national sample and the fact that folic acid doses taken by the mothers were quantified.

A finding that supports a link between folic acid and ASD is that fish oil supplementation did not seem to have a protective effect in terms of diagnosis of any of the ASDs, even though its use was associated with the same demographic features as folic acid supplementation. This seems to suggest a real potential effect of folic acid.

The investigators comment that the overall prevalence of autism in Norway is much lower than in other countries, and that the small percentage of children with each condition found in this study reflects the lower overall rate compared with recent rates in US children. Nonetheless, these intriguing findings bear further exploration in other studies to see whether the relationship holds in other populations.