What causes autism?
Autism spectrum disorder (ASD) is a broad term used to describe a group of neurodevelopmental disorders.
These disorders are characterized by problems with communication and social interaction. People with ASD often demonstrate restricted, repetitive, and stereotyped interests or patterns of behaviour.
ASD is found in individuals around the world, regardless of race, culture, or economic background. According to the Centers for Disease Control and Prevention (CDC), autism does occur more often in boys than in girls, with a 4 to 1 male-to-female ratio.
The CDC estimated in 2014 that nearly 1 in 59 children have been identified with ASD.
Because autism runs in families, genes likely play a role. Other risks include:
There is no evidence that vaccines cause autism. The exact reason why autism happens isn’t clear.
- Mothers and fathers who have children late in life
- A pregnant woman who drinks alcohol or have conditions like diabetes and obesity
- Pregnant women who take antiseizure drugs
- Untreated phenylketonuria (called PKU, a metabolic disorder caused by the absence of an enzyme) and rubella (German measles)
According to the National Institute of Neurological Disorders and Stroke (NINDS), both genetics and environment may determine whether a person develops autism. The causes of autism are still being investigated. Many experts believe that the pattern of behaviour from which autism is diagnosed may not result from a single cause, and that there are genetic factors.