ASD occurs in all racial, ethnic, and socioeconomic groups. It is more than 4 times more common among boys than among girls.
A great deal of evidence supports the idea that genes are one of the main causes of or a major contributor to ASD. More than 100 genes on different chromosomes may be involved in causing ASD, to different degrees. Many people with autism have slight changes, called mutations, in many of these genes.
Research suggests that autism genes are usually inherited from the father, despite some research showing it's passed down from the mother.
According to the CDC, the prevalence of autism in the United States is approximately 1 in 54 children. This means that the odds of having a child with autism are less than 2%. If you are concerned about the odds of having a child with autism, there are steps you can take to reduce your risk.
Several risk factors present during pregnancy have been associated with autism. Some, like older parental age and use of antidepressants, have strong research support. Others, such as Tylenol (acetaminophen) use and exposure to environmental toxins, need more investigation.
Children born to older parents are at a higher risk for having autism. Parents who have a child with ASD have a 2 to 18 percent chance of having a second child who is also affected. Studies have shown that among identical twins, if one child has autism, the other will be affected about 36 to 95 percent of the time.
Autism is not an illness
It means your brain works in a different way from other people. It's something you're born with. Signs of autism might be noticed when you're very young, or not until you're older. If you're autistic, you're autistic your whole life.
While autism is typically not diagnosed before the age of 2 (and often much later), it can sometimes be detected earlier. A 2022 study found that a routine second-trimester ultrasound could detect early signs of autism during pregnancy,18 including anomalies in the heart, head, and kidneys.
If someone in your family has autism spectrum disorder (ASD), you may be more likely to have a child with ASD. ASD can look very different from person to person, so taking a careful family health history can be important for early diagnosis.
Autism may stem from a different — and larger — set of genetic mutations in women than it does in men, according to a new study1. The findings support a growing body of evidence suggesting that women require a bigger genetic hit than men do to have conditions that affect brain development, including autism.
A number of studies have suggested that it takes a bigger genetic 'hit' to cause autism in girls than in boys — on average, girls who have autism tend to have more gene changes than boys do.
Depression isn't the only mental health factor that can influence pregnancy outcomes. High levels of stress during pregnancy may also be connected to autism in children. This connection appears to have the most impact when the parent experiences stress between weeks 25 and 28 of pregnancy.
Genetic factors, environmental chemicals, certain drugs and vaccines, maternal factors, and environmental stress may all be legitimate causes. Many conditions can present alongside autism, and dealing with them can help ensure a proper autism diagnosis.
The behavioral symptoms of autism spectrum disorder (ASD) often appear early in development. Many children show symptoms of autism by 12 months to 18 months of age or earlier. Some early signs of autism include: Problems with eye contact.
1 in 100 children are diagnosed with autism spectrum disorder as of 2021. Autism prevalence has increased 178% since 2000. The country with the highest rate of diagnosed autism in the world is Qatar, and the country with the lowest rate is France.
We respond by avoiding the distressing stimuli—avoidance being another core feature of PTSD. All of this hints at a complex and poorly understood relationship between autism and PTSD. While autism is never caused by trauma, there may be something about living with autism that is inherently traumatic.
Current research suggests that a combination of genetic and environmental factors may increase the chances a person will meet the criteria for ASD. These may include specific genetic variants, older parental age, preterm birth, and others. However, researchers are still learning about the possible causes.
Autism is not caused by malnutrition or food-related challenges, but, for many people, there is a connection between autism and food. Research suggests that food-related challenges have a significant impact on many people who are diagnosed on the autism spectrum.
At the same time, firstborn children also showed an increased incidence — 30 percent more than second-borns and 70 percent more than those born third or later.
A substantial amount of research shows a higher rate of autistic type of problems in males compared to females. The 4:1 male to female ratio is one of the most consistent findings in autism spectrum disorder (ASD).
Older parents, especially older fathers, are more likely than other parents to have children with autism. This finding, which has been replicated in several large studies, establishes an association between age and autism.