I have a son with autism
Oh I see. They say parents n  otice the symp toms in the first   two or three years.t
my son's signs gradually developed- he wasn't meeting milestones at the same rate as his peers
It's not really known what causes it, I believe. A combination of genetic and environmental factors.
growth restriction, and autoimmune diseases. Controversies surround other proposed environmental causes; for example, the vaccine hypothesis, which has been disproven. Autism affects information processing in the brain by altering connections and organization of nerve cells and their synapses. How this occurs is not well understood. In the DSM-5, autism and less severe forms of the condition, including Asperger syndrome and pervasive developmental disorder not otherwise specified (PDD-NOS), have been combined into the diagnosis of autism spectrum disorder (ASD).
Early behavioral interventions
Autism
Autism is a developmental disorder characterized by difficulties with social interaction and communication, and by restricted and repetitive behavior. Parents usually notice signs during the first three years of their child's life. These signs often develop gradually, though some children with autism reach their developmental milestones at a normal pace before worsening.
Autism is associated with a combination of genetic and environmental factors. Risk factors during pregnancy include certain infections, such as rubella, toxins including valproic acid, alcohol, cocaine, pesticides and air pollution, fetal