Maternal folic acid, multivitamin use linked to reduced autism risk
Use of folic acid or multivitamins during pregnancy is associated with a significantly reduced risk of ASD in offspring.
Folic acid and multivitamin supplements, taken by women before and during pregnancy, may help reduce the risk of autism spectrum disorder (ASD) in their offspring, according to a study published in JAMA Psychiatry.
Stephen Z Levine, PhD, of the Department of Community Mental Health at the University of Haifa in Israel, and associates assessed the link between folic acid and multivitamin supplement intake and associated risks of ASD in the offspring of women before and during pregnancy.
The researchers conducted a case-control group study in which 45,300 Israeli children (born between 2003 and 2007) were monitored for signs of ASD from birth until January 1, 2015. Cases were defined as all ASD-diagnosed children, while controls were a random sample of 33% of the all live-born children. Of the entire cohort, 51% of children were boys (average age, 10 years).
The main outcome was the affiliation between maternal vitamin supplementation and the relative risk of ASD development in offspring. In addition, the researchers compared consumption of folic acid with multivitamin supplements.
Twenty-six percent of children were born to mothers who took folic acid or multivitamins before pregnancy, and 48.3% were born to mothers who took folic acid or multivitamins during pregnancy.
The investigators reported that 1.3% of the children were diagnosed with ASD. Compared with mothers who were not exposed to folic acid or multivitamins, mothers taking these supplements had a statistically significant decrease in risk for ASD in offspring.
The relative risks associated with folic acid and multivitamin supplement intake before and during pregnancy (compared with not taking any at all) are 0.39 and 0.27, respectively. Analogous relative risks were recorded for mothers taking folic acid before pregnancy (RR, 0.56), folic acid during pregnancy (RR, 0.32), multivitamins before pregnancy (RR, 0.36), and multivitamins during pregnancy (RR, 0.35). These results were statistically significant in favor of folic acid or multivitamin exposure compared with no exposure at all.
“Unique to our study, to our knowledge, is the ability to examine the association between multivitamin exposure and ASD for an extended period preceding pregnancy,” the authors stated. “Future research is warranted to examine the association between vitamin exposure before pregnancy and outcomes in offspring further.”
- Levine SZ, Kodesh A, Viktorin A, et al. Association of maternal use of folic acid and multivitamin supplements in the periods before and during pregnancy with the risk of autism spectrum disorder in offspring. JAMA Psychiatry. 2018 Jan 3. doi:10.1001/jamapsychiatry.2017.4050