Why more women are being diagnosed with autism later in life

For decades, autism was viewed primarily as a condition affecting boys. Early researchers from the 1940s studied almost entirely boys and men, shaping diagnostic guidelines around traits more commonly seen in males. Behaviors that stood out in boys—like repetitive movements, intense fixations on objects or difficulties with social interaction—became the “classic” signs of autism.

As a result, boys have long been diagnosed at much higher rates. According to the CDC, girls are four times less likely to be diagnosed with autism than boys and, on average, receive a diagnosis nearly a year later.

But today, that gap is narrowing. More women than ever are getting a diagnosis—and for many, that diagnosis is arriving later in life. Research shows that between 2011 and 2022, autism diagnoses in girls and women more than tripled - rising faster than diagnoses in boys and men, which nearly doubled over the same period. And a large study out of Sweden shows that by age 20, diagnosis rates for men and women were almost equal, challenging previous assumptions that autism is more common among males.

Experts say this doesn’t mean autism is suddenly more common in women. Instead, it suggests that many girls were simply overlooked.

Why women are often missed

Autism doesn’t always look the same in girls as it does in boys. Girls and women may show fewer obvious repetitive behaviors. They may have stronger conversational skills or be more likely to share their interests with others. Their special interests may appear typical for their age and therefore go unnoticed.

“I think that sometimes examples of behavioral features in autism (like a strong interest in trains and spending a long time lining them up) are less commonly recognized in females,” says Dr. Vanessa Bal, expert in adult autism and professor of psychology at Rutgers University. “Parallel examples in girls, like a strong interest in Barbies and spending a long time arranging them, is often not recognized due to differences in expectations.”

Social expectations also play a role. From a young age, girls are often encouraged to be socially aware and accommodating. Many learn to carefully observe others and copy their behaviors, even when social interactions feel confusing or exhausting. This is often called masking.

Masking can include forcing eye contact, holding back stimming behaviors, copying other people’s facial expressions or rehearsing what to say before a conversation. While masking can help someone fit in, it can also be draining. Research shows that long-term masking is linked to higher rates of anxiety, depression, stress and even suicidal thoughts.

While masking can help someone navigate social situations, it often comes at a cost. Studies link long-term masking to anxiety, depression, chronic stress and even suicidality. It can also delay diagnosis—sometimes for decades—because outward signs of autism are less visible to teachers, clinicians and even family members.

Masking can also make autism harder to recognize. Teachers, doctors and even family members may not see the signs clearly. As a result, many girls without intellectual disability or language delays are missed or diagnosed with something else, such as anxiety or ADHD.

That can have real consequences. Delayed diagnoses can mean that autistic people have to work harder to get the right supports, and may miss out on critical early intervention services that could have a lifelong impact on their quality of life.

The road to a diagnosis

Dr. Bal says many women who pursue an evaluation later in life describe a similar experience: they’ve always felt different, but never quite knew why. Often, there is no single event that leads someone to seek a diagnosis. A conversation, a passing mention of autism or an internet search can spark curiosity, which over weeks or months may lead someone to seek an evaluation.

But sometimes, a significant life event—like losing a job, having a mental health crisis, or having a child who is diagnosed with autism—prompts someone to start looking more closely.

“I was diagnosed simply because my son has autism and I realized that I never thought there was anything wrong with him,” says Elisheva Levin, a self-advocate who received her diagnosis at age 45. “I think the gap in diagnosis comes down to the fact that girls mask better. We’re trying so hard just to manage and not look incompetent. In our society, women are often seen to be less capable—whether they’re on the spectrum or not. Add to it that autistic women have a different way of interacting with the world, and you set us up to constantly feel like we should be doing more.”

For women who suspect they may be autistic, Dr. Bal recommends consulting a psychologist and psychiatrist with expertise working with autistic adults.

“It may be difficult to find someone specializing in adults, but start with the nearby autism clinic, and if they only see children, ask about their recommendations for adult evaluations,” explains Dr. Bal. “I would look for someone with autism expertise; providers who work with adults with ADHD might also be a good place to start.”

Before an evaluation, it can help to reflect on why you’re seeking a diagnosis—whether to access services, request accommodations or simply better understand yourself. Gathering information about childhood experiences may also be useful.

“Going into a diagnostic evaluation, it can be helpful to know if you have ever received supports in school and if anyone in your family ever noted any differences or difficulties in your childhood,” says Dr. Bal. “This is not to suggest you have to have a family member validate your experience, but sometimes family members remember things that you might not. For example, sometimes a parent will recall that a preschool teacher noted something, or that they were worried about something that you did not know about.”

If your concerns are dismissed, don’t give up. Many clinicians are trained primarily in diagnosing autism in children and may have limited experience recognizing it in adults—especially women.

“If a diagnostician is not helpful and dismissive, it may be useful to find a therapist who has autism expertise or experience working with neurodivergent adults,” adds Dr. Bal. “Sometimes finding therapists can be easier—there are more virtual options and they often take insurance and have less of a wait to be seen. Working with a therapist over several weeks or even months can help sort through concerns. For people who just want the diagnosis to understand themselves, there isn’t a specific test or set of tests that have to be administered. Diagnoses can be made over time by a therapist who knows you well.”

For adults exploring a possible diagnosis, Autism Speaks offers resources to help guide the process. The Autism Speaks Adult Diagnosis Tool Kit provides practical information on what to expect during an evaluation, how to prepare and how to find qualified providers. The Autism Response Team is also available to connect individuals and families with information and guidance about local providers, so that you do not feel alone in your search for a diagnosis.

Dr. Vanessa Bal is the Karmazin & Lillard chair in adult autism and a professor at the Department of Applied Psychology at Rutgers University. She is a licensed clinical psychologist and director of the Rutgers Center for Adult Autism Services Psychological Services Clinic. She currently sits on the Autism Speaks Early Career Investigators Advisory Subcommittee. Dr. Bal’s research focuses on advancing the understanding of autism in adulthood.