A recent population-based, long term cohort study conducted by the Norwegian Institute of Public Health studied the correlation between folic acid supplementation and the risk of autistic traits in children exposed to antiepileptic drugs (AEDs) in utero. Children exposed to AEDs in utero have an increased risk of exhibiting autistic traits. These traits include impairment of social skills and communication as well as stereotyped or repetitive behavior or interests.

The Norwegian Mother and Child Cohort Study, included 104,946 children and studied Norwegian-speaking women from June 1999 to December 31, 2008. Researchers performed questionnaires during and after pregnancy, analysis of blood samples, and linkage to the Medical Birth Registry of Norway. The women also completed an epilepsy-specific follow up questionnaire in 2013.

From March 1, 2016 through June 13, 2017, children aged 18 to 36 months of women with available information on their use of AEDs and folic acid supplements were analyzed. Researchers studied mothers’ exposures to maternal folic acid supplementation 4 weeks before to 12 weeks after conception and analyzed the plasma folate concentration at gestational weeks 17 to 19.

Using the Modified Checklist for Autism in Toddlers and Social Communication Questionnaire, researchers evaluated autistic traits in the children. The results showed that the degree of autistic traits was inversely associated with maternal plasma folate concentrations and folic acid dosed. The concentration of AEDs was not associated with the degree of autistic traits.

The study concluded that folic acid supplementation and folate status may mitigate the risk of autistic traits in children exposed to AEDs in utero. The researchers urge women taking AEDs to take folic acid supplements persistently.

The results of this study coincide with the results of an uncontrolled study of 105 children whose mothers took AEDs while pregnant, but did not supplement folic acid in the first trimester. Mothers who use AEDs during pregnancy have a 5 to 8 times greater risk of having a child with autistic traits. According to the study, it is incredibly important for women to begin using folic acid supplements before and during pregnancy.

The supplementation of folic acid by pregnant women has long been an important cause for the dietary supplement industry and the results of this study further reinforces the importance of supplementation. “Supplementing with folic acid by women who are pregnant, or capable of becoming pregnant, has proven essential to reduce neural tube birth defects in babies, and this new study demonstrates the potential for additional benefits of continuous folic supplementation," explains Andrea Wong, Ph.D., vice president, scientific and regulatory affairs, Council for Responsible Nutrition, in a statement. "Although this study points to the reduction of autistic traits associated with folic acid supplementation in a specific population— women taking antiepileptic drugs — it underscores the importance for all women capable of becoming pregnant to supplement with folic acid, too. The recommendation for all women of childbearing age to supplement with folic acid is supported by the U.S. Government, the American College of Obstetricians and Gynecologists, the American Academy of Family Physicians, and the American Academy of Pediatrics, and should be heeded to promote the health and wellbeing of future children."