"Taking prenatal vitamins https may reduce the risk of having a child with autism https new research shows. It appears that women who reported taking prenatal vitamins starting three months prior to conception https and through the first month after conception https seem to have a reduced chance their child will develop autism https says study researcher Irva HertzPicciotto PhD professor of epidemiology and environmental health at the MIND Institute and Department of Public Health University of California Davis. Taking prenatal vitamins was found even more protective for mothers and children who had a highrisk genetic makeup https The study is published online in Epidemiology. The research needs to be duplicated HertzPicciotto tells WebMD. Still she says the finding points to a geneenvironment interaction that may possibly help explain some cases of autism. Autism spectrum disorders https marked by impaired language repetitive behaviors and social difficulties now affect up to one in  children according to the CDC. Prenatal Vitamins and Autism Risk The researchers looked at three groups of children all aged  to . All were enrolled in the CHARGE study CHildhood Autism Risks https from Genetics and Environment from  to . The groups included   children with autism   with autism spectrum disorder   children with typical development Mothers reported their use of prenatal vitamins or other supplements https before during and after pregnancy https The researchers collected blood https from all family members to evaluate their genetic makeup. They focused on genes known to play a role in folate metabolism https These genes include MTHFR and COMT as well as others. Folate and other B vitamins https are crucial to brain https development. Overall HertzPicciotto says For the women who didnt take prenatal vitamins there was about a  higher risk of having a child with autism. The risk rose if the mothers or the children had a highrisk gene form. The mothers with the highrisk form of MTHFR had a . times higher chance of a child developing autism she says than mothers without this highrisk form who did take the prenatal vitamins. Children who had the highrisk COMT gene form were seven times as likely to have autism as children without it whose mothers did take the vitamins. Overall it does look like there are at least a couple of genes here either the mothers genotype or the childs genotype that show this interaction ... magnifying the size of the effect from not taking the vitamins HertzPicciotto says. Exactly why the prenatal vitamins may protect against autism is not clear she says. It may be that the vitamins contribute to high levels of folate. Genes Vitamins Play Roles Many other studies have shown the benefits of prenatal vitamins on preventing birth defects https says Alycia Halladay PhD director of research for environmental sciences for Autism Speaks an advocacy and research organization. However she says There hasnt been any published data about a prenatal vitamin and autism. She reviewed the study findings for WebMD but was not involved in the research. It adds to the body of evidence that prenatal vitamins are an important health habit for women of childbearing age she says. To me the big news of the study is they were able to document a geneenvironment interaction. They found an effect with vitamins alone Halladay says in protecting against autism. When they looked at the genetic makeup of those mothers and children the differences became even bigger. Women of childbearing age who may become pregnant or those planning pregnancy should ask their doctors advice about taking prenatal vitamins she says."