April 10, 2023
Girls with autism are often misdiagnosed because their symptoms manifest differently than they do in boys. Scientists say the prevalence of the disorder among girls is most likely higher than what studies show.
Autism is a neurodevelopmental disorder that can affect a person's ability to communicate and interact socially with others. Historically, it has been thought to affect boys more than girls. But in the last decade, as awareness of gender differences in the way the disorder manifests has grown, the number of girls diagnosed with autism has increased.
In 2012, boys were estimated to be 4.7 times more likely than girls to receive an autism diagnosis, according to the U.S. Centers for Disease Control and Prevention. Now in 2023, boys are only 3.8 times more likely to be diagnosed with autism. That means 1% of girls are estimated to have autism, the highest number reported to date, according to The New York Times.
Since autism was first included in the Diagnostic and Statistical Manual of Mental Disorders in 1980, its recognized symptoms have expanded to include a wide spectrum of behaviors including verbal and nonverbal language, impairment, lack of interest in people, difficulties maintaining relationships and fixations on certain things.
Autism in girls is still more often missed, leading to delayed diagnoses or no diagnoses at all. Most criteria for an autism diagnosis are based on research that focused mostly on boys. Though boys with autism are more likely to exhibit repetitive behaviors, such as lining up toys, and restricted behaviors, such as only having an interest in certain toys, girls with autism tend to manifest symptoms in a slightly different ways, especially if they have are high-functioning.
Girls with autism may have an intense interest in something, but it usually lines up more easily with the interests of other girls. They just have a more intense focus on it.
"The model that we have for a classic autism diagnosis has really turned out to be a male model," Susan F. Epstein, a clinical neuropsychologist, told the Child Mind Institute. "That's not to say that girls don't ever fit it, but girls tend to have a quieter presentation, with not necessarily as much of the repetitive and restricted behavior, or it shows up in a different way."
Girls also are more likely to control their behaviors in public so their differences are not as noticeable. They are more likely to wait until they get home to release pent-up emotions instead of having outbursts at school. Because boys may be more disruptive in class, they draw more attention.
The most common signs of autism among females are relying on other people to guide or speak for them, frequently experiencing sensory overload, having passionate but limited interests, having difficulty making and keeping friends, and having difficulties controlling emotions. They often appear to be shy, quiet or passive.
Often these symptoms are just chalked up as being just a part of a person's personality. Because of gender stereotypes, girls who are quieter, spend more time in their heads and are less assertive often are seen in a more positive light than boys who act the same way. Boys exhibiting these symptoms are more likely to get intervention, experts say.
One study found that irritability and lethargy are often symptoms of autism in females, too.
Some girls do exhibit the more classical signs of autism, including extreme language impairment, and in those cases they are more likely to get the help they need at an early age.
More recent studies have shown that girls with mild autism often are able to mask their symptoms and successfully imitate their peers who don't have autism. Because of the male-oriented stereotypes associated with autism, this often leads these girls to be diagnosed much later than boys, and sometimes not until adulthood.
A contributing factor may be that the part of the brain responsible for social behavior develops more quickly in girls than boys, making it easier for them to camouflage any social challenges they are experiencing. Girls want to fit in with the other kids so they try to mimic the behaviors of others without truly understanding social contexts. They tend to have just one or two close friends.
By the time these girls hit middle school and high school, when friendships become more complex, however, their differences become more noticeable, often leading to bullying. Girls with autism are more likely than boys with the disorder to develop anxiety or depression. Often times, they are first labeled with a mental health disorder and autism is not considered as an underlying cause.
When an autism diagnosis is delayed or completely missed, it means girls and women with autism are not getting the early interventions that may help them. Scientists say more research is needed to better understand the gender differences found in autism. Many researchers, like those involved in a 2021 study, say that more female-oriented examples need to be added to the diagnostic tools used to identify autism.