Women who didn\'t take prenatal vitamins early in pregnancy had an elevated risk of having a child with autism spectrum disorder, U.S. researchers say. Lead author Rebecca J. Schmidt, an assistant professor at the University of California, Davis, School of Medicine, says the researchers collected data from approximately 700 California families with children ages 2-5, who had autism or typical development. The autism diagnoses were confirmed through testing at the UC Davis MIND Institute, Schmidt says. Women who participated in the study were asked by telephone whether they took prenatal vitamins, multivitamins or other supplements at any time during the three months prior to and during their pregnancies and during breastfeeding. \"Mothers of children with autism were significantly less likely than those of typically developing children to report having taken prenatal vitamins during the three months before and the first month of pregnancy,\" Schmidt says in a statement. The study, scheduled to be published in the journal Epidemiology in July, found for women with a particular high-risk genetic makeup who reported not taking prenatal vitamins, the estimated risk of having a child with autism was as much as seven times greater than in women who did report taking prenatal vitamins, but who had more favorable gene variants.