The idea that preconception environmental exposures may be involved in Autism Spectrum Disorders (ASD) etiology arose in the 1970s from a retrospective case-control study of ASD that found a statistically significant difference in parental occupational exposure to chemicals during the preconception period 1. ASD are neurodevelopmental disorders characterized by varying deficits in social interactions, communication, and learning, as well as stereotypic behaviors. Over the past years, research into environmental risk factors for autism has grown dramatically, bringing evidence that an array of non-genetic factors acting during the prenatal period may influence neurodevelopment 2. The present study was therefore undertaken to investigate the potential prenatal risk factors for ASD. A total number of 184 individuals were studied. In the present study, factors that have demonstrated significant increases in ASD risk, include advanced maternal age and stress during pregnancy while folic acid and calcium supplement intake was found to be reducing the risk of ASD. Factors that showed insignificant increase in frequency or no association with ASD were intake of medications, fall, respiratory problems and bleeding during pregnancy.