In a study recently conducted by the University of North Carolina on Swedish families, researchers interpreted that having a schizophrenic parent or a mother with psychiatric problems likely doubles a child's risk of being autistic. Several families, consisting of over 1,200 children, all with some relation to autism and all born between 1977 and 2003 were part of the study. They were compared against families of nearly 31,000 children, none of which had autism.