A new 2013 study led by scientist Pal Suren found that women who consumed 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 classic autism, the most severe form of autism. The findings showed no impact on autism spectrum disorders.
For years medical practitioners have advised pregnant women to take folic acid as part of their daily vitamin regiment. The U. S. Public Health Service and CDC recommend that all women of childbearing age consume 0.4 mg (400 micrograms) of folic acid daily to prevent two common and serious birth defects, spina bifida and anencephaly.
“It appears that the reduced risk of childhood autism only reflects folic acid supplements, not food or other supplements, and that the crucial time interval is from four weeks before conception to eight weeks into pregnancy,” says Dr Pål Surén, primary author of the paper and researcher at the Norwegian Institute of Public Health.
The ABC study was conducted by the Norwegian Institute of Public Health in collaboration with Columbia University in New York and the National Institute of Neurological Disorders and Stroke (NINDS) in Bethesda, USA.
The study investigated 85,176 children, who were born in 2002-2008, with mothers providing detailed information about their diet and use of supplements. Results demonstrate that 270 children with autism diagnoses were identified in the study population. Of these children, 114 children had autism, 56 had Asperger syndrome and 100 had atypical or unspecified autism.
Surén P, Roth C, Bresnahan M, et al. Association between maternal use of folic acid supplements and risk of autism in children. JAMA, 2013 DOI: 10.1001/jama.2012.155925