Folic Acid May Protect Against Autism

Autism risk was lower when mothers took folic acid before and during pregnancy

/ Author:  / Reviewed by: Robert Carlson, M.D

(RxWiki News) Taking folic acid before and during pregnancy may help lower the risk of some birth defects. Researchers wanted to know if folic acid was linked to autism in any way.

A recently published study showed that women who took folic acid for one month before and two months after becoming pregnant were about 40 percent less likely to have their child diagnosed with autism.

The authors suggested that folic acid supplements may help protect against autism.

"Ask an OB/GYN about which vitamins are right for you."

Researchers led by Pål Surén, MD, MPH, of the Norwegian Institute of Public Health in Oslo, talked to pregnant mothers about which vitamins they were taking around the time they conceived their babies.

The researchers followed 85,176 children for an average of about six years to see which children were diagnosed with an autism spectrum disorder (ASD). Children in the study ranged from 3 to 10 years old at the end of the study.

The children were considered to be exposed to folic acid if their mother took a supplement of folic acid for at least one month before conceiving and two months after conceiving.

At the end of the study, 270 kids were diagnosed with ASD. Results showed that women who took folic acid were less likely to have a child diagnosed with autistic disorder, but folic acid did not appear linked to other forms of ASD, such as Asperger’s or pervasive developmental disorder.

A total of 64 out of 61,042 (about 0.1 percent) mothers who took folic acid had a child who developed autistic disorder.

Of the 24,134 mothers who did not take folic acid, 50 (about 0.2 percent) had a child who developed autistic disorder.

The odds of having a child with autistic disorder after taking folic acid were about 0.61. In other words, the risk of having autism was reduced by about 40 percent when folic acid was used by the mother.

The authors concluded, “Although these findings cannot establish causality, they do support prenatal folic acid supplementation.” In other words, it was not clear if the folic acid was truly the cause of the lower risk of autism. But the authors suggested that taking folic acid was safe and may help lower the risk for ASD.

Folic acid is one of the B vitamins. It is found in many prenatal vitamins and some foods.

The study was published February 12 in JAMA. The authors reported no conflicts of interest. The study was funded by the Norwegian Ministry of Health and Care Services, the Norwegian Ministry of Education and Research, the Research Council of Norway, the National Institute of Neurological Disorders and Stroke and the National Institute of Environmental Health Sciences.

Reviewed by: 
Review Date: 
February 13, 2013
Last Updated:
February 14, 2013