A new study reveals that autism may begin during pregnancy. Scientists analyzed postmortem tissue samples from children with autism as well as typically developed children. What they discovered is that, as far back as the second trimester, certain cells are not where they are supposed to be in the brains of autistic children. During normal brain development in the womb, a child’s brain cells migrate to a specific part of the brain. However, in the brains of autistic children, this movement does not happen. This research has allowed scientists to pinpoint when this hitch in development appears, which will in turn help them understand why and how autism occurs.