WHY IS AUTISM MORE COMMON IN MALES?

ASPERGER’S IN GIRLS & WOMEN
The gender ratio of 3-4.3 males to 1 female is a relic of the initial description of autism, but has been entrenched as fact. That is changing, especially in girls and women. Autism diagnoses are on the rise—soaring by as much as 175 percent just in the last decade, with the most significant increases among 24-to-36-year-olds, women, and children. This is in part due to a growing awareness of autism. But we’re also getting better at understanding how autism can look very different from what we once thought.

Fetal Testosterone. Cambridge has analyzed research into fetal testosterone effects on brain development and postnatal autistic behaviour. It measured testosterone produced by the fetus and measured via amniocentesis during the first trimester of pregnancy. Fetal testosterone shapes brain development by binding to androgen receptors to alter an individual’s cognitive profile. The amygdala is one region that is rich in such receptors. They showed that higher prenatal testosterone levels are associated with reduced social skills but superior attention to detail in infants.

Autism Spectrum Conditions (ASC) are all too often missed, mislabelled, identified late or entirely overlooked in females. In epidemiological studies, the gender ratio is 2-3:1, in adult diagnostic clinics, the ratio is 2:1, and it is thought that the ratio could fall to 1.8 males to every female. Girls and women are older when diagnosed and go through more assessment rounds. Symptoms may not be present in the early development period, and they may not manifest fully until social demands exceed limited capacities or may be masked by learned strategies in later life.

The classification system, diagnostic tools, and research have all promoted the male phenotype of autism. Most of what we know about autistic females has been gathered from females who have met the male phenotype for autism, in other words, females who have been diagnosed using the existing classification system and subsequent diagnostic tools, which have a male bias.

One reason why the prevalence of Asperger’s in girls and women is so low in comparison to boys and men may be the fundamental lack of awareness of what Asperger’s “looks like” in females. Girls with Asperger’s may be more challenging to recognize. Parents, teachers, and clinicians may fail to see any conspicuous characteristics of AS in females. The stereotype is that autism is a childhood disability that traps people in their world, that people are disconnected from society and community, and that they are sad and suffering. The reality of autism couldn’t be further from that. 

Suppose a gender is known to be predominant (which, in autism, we know it is), regardless of pathology. In that case, it is only responsible to explore the potential for bias in the diagnosis or the sampling. 

BIAS IN DIAGNOSTIC CRITERIA/DIAGNOSTIC TOOLS
Why are females overlooked or diagnosed late?
Autism has been thought of as a male condition since the seminal work of Kanner and Asperger in the mid-1940s. Both men identified autism in boys, and only later did Asperger’s acknowledge that girls, too, could be autistic. Their condition characterization was then reflected in the classification system known as the Diagnostic and Statistical Manual (DSM).

Diagnostic tools were developed that meshed with the DSM criteria for autism. For instance, the ADI-R (Autism Diagnostic Interview-Revised) and the ADOS (Autism Diagnostic Observation Scale) are well related to the DSM-IV (Diagnostic and Statistical Manual, 4th edition). The ADI-R, in conjunction with the ADOS, are considered the ‘gold standard’. So, with great intention, diagnostic tools perpetuated the criteria in the classification system, which stemmed from Kanner and Asperger, further reinforcing that primarily males receive a diagnosis of autism.

The way the diagnostic tools are designed, they lean toward diagnosing the typical male ASC presentation. They do not account for the variability of autistic symptoms by gender. If females present symptoms not included in the diagnostic algorithms for tools like the ADI-R, then a diagnosis of autism cannot be made.

The ADI-R has four items crucial to differentiate males and females that are insensitive to females without intellectual disability (an IQ less than 70). That is where we get the discrepancies in autism between males/females and females with/without intellectual disability. The ADOS relies on observation, and as most autistic females are adept at masking, the ADOS is insensitive to identifying females.

BIASED SAMPLING IN RESEARCH
Sampling bias occurs when one gender dominates a specific condition. In a meta-analysis of 392 articles on autism, 80% of the study participants were male.
Clinicians and educators are looking for males in the belief that autism is a male condition. There is a fundamental lack of awareness of what Asperger’s Syndrome “looks like” in females.

♦ Girls and women may be overlooked as they may better understand basic social skills. Social communication skills, though superficial, allow them to fly under the radar.
Females with AS demonstrate relative strengths in socio-communicative abilities compared to males with AS. They are better than males at nonverbal communication strategies and gestural use, and better at reciprocal conversations. They have short conversations or make limited eye contact but struggle with more complex social situations, such as creating and maintaining friendships.
Females are more socially motivated and have a greater capacity for traditional friendships. When you add their ability to imitate, camouflage and mimic, to their increased motivation for social interaction, the presentation proves to be an excellent disguise for their autistic traits.
They can hide in plain sight; they do not stand out socially to the same degree as their male counterparts because they can fake it so well. By adolescence, camouflaging and overexerting oneself socially can become mentally and emotionally exhausting, and it can impact other areas of life, including mental health and functioning.

♦ The female with Asperger’s may be shy, quiet, and perfect at school. She may avoid active participation in class proceedings, and thus, teachers and peers may leave her alone. Teachers may fail to recognize autistic females as they have fewer concerns about the behaviour of girls. Even when clinicians recognize social/communication deficits, teachers fail to acknowledge this.
But the AS girl could also be tomboyish, moody, overly competitive, aloof, Gothic, depressed, anxious, or a perfectionist, masking her autistic social issues.

♦ Girls tend to ‘disappear’ in a large group, being on the periphery of social interaction – ‘on the outside looking in’.

♦ A girl with AS is less likely to be ‘fickle’ or ‘bitchy’ in friendships in comparison to other girls.

♦ A girl may conceal confusion when playing with peers by politely declining invitations to join in until sure of what to do, so as not to make a conspicuous social error. The strategy is to wait, observe, and only participate when sure of what to do by imitating what the children have done previously. If the rules or nature of the game suddenly change, the child is lost.

♦ Girls are likelier than boys to develop a close friendship with someone who demonstrates a maternal attachment to this socially naive but ‘safe’ girl. This reduces the likelihood of being identified as having one of the main diagnostic criteria for AS, namely a failure to develop peer relationships. With girls, it is not a failure but a qualitative difference in this ability. The girl with social understanding may only become conspicuous when her friend and mentor move to another school

♦ They may passively avoid cooperation and social inclusion at school and home, as described in a condition known as Pathological Demand Avoidance.

BELIEF THAT IT IS A MALE CONDITION
Males generally present with more overt autistic traits. As males tend to be externalizers, they may present as more disruptive in a school environment. They have externalizing behaviours (hyperactivity/impulsivity and conduct problems). Females instead are more likely to have internalizing problems like anxiety, depression and eating disorders.

Girls with the same degree of symptom severity as boys are less likely to get the diagnosis. Autism has been overlooked in females.

♦ In a study of playground behaviour, it was found that autistic boys were more likely to stand out as ‘loners’ among their peers. Girls, however, may bounce from social group to social group and flit about like the proverbial social butterfly, which, to the onlooker, makes them appear to be socially confident and competent, when they may be shifting groups because of rejection.

♦ In conversation, boys may sound like ‘little professors’ with an advanced vocabulary and can provide many interesting (or boring) facts. Girls with AS can sound like ‘little philosophers’, with an ability to think deeply about social situations. Girls with AS have applied their cognitive skills to analyze social interactions from an early age. They are more likely than boys with AS to discuss the inconsistencies in social conventions and their thoughts on social events.

♦ Females are less likely to have developed conduct problems that can prompt a referral for a diagnostic assessment for a boy. Suppose the expression of symptoms of a disorder differs by gender. In that case, the development of diagnostic criteria will be biased toward the gender that externalizes psychic distress and exhibits socially unacceptable behaviour.

♦ The special interests of girls with AS may not be as idiosyncratic or eccentric as those of some boys. Girls and women can be overlooked when they develop special interests that aren’t stereotypically associated with autism, such as becoming obsessed with ponies or fashion, rather than trains and computers.
Adults may consider a girl with an interest in horses nothing unusual. Still, the problem may be the intensity and dominance of the interest in her daily life: the girl may have moved her mattress into the stable to sleep next to the horse.
If she is interested in dolls, she may have over 50 Barbie dolls arranged alphabetically, but she rarely includes other girls in her doll play.

REPETITIVE and RESTRICTED BEHAVIOURS and INTERESTS (RRBIs)
RRBIs are included in the DSM, and many people think of RRBIs as the indicator of autism. Females have RRBIs, but they have fewer RRBIs than males.

Their special interests are not that special. Females have circumscribed interests, even intense interests, but they do not differ significantly from their neurotypical peers. Ponies, boy bands, animals, fashion, makeup, nail polish can all be transfixing for the autistic female. Still, as a focused interest, they do not make her appear appreciably odd.

Furthermore, females engage in fewer rituals than males and take less interest in ‘parts of objects’ (e.g., spinning wheels on a toy car). This poses a problem for securing a diagnosis because the DSM and diagnostic tools all emphasize RRBIs, and males may be more likely to endorse this distinction dramatically, while females may not.

MASKING (CAMOUFLAGING)
Young children with ASC characteristics may be able to use constructive coping and adjustment strategies to camouflage their deficits in social interaction and communication. Masking, camouflaging, or adaptive morphing occurs when people act as they believe others want them to. This behaviour reduces the observability of autistic traits, which may make it harder to identify autism in female-presenting people.

They observe and analyze, then adopt what they believe is acceptable to society.
Camouflaging is experienced as an obligation rather than a choice. Autistic females are more likely than males to camouflage; 90% of AS females have engaged in camouflaging.

They may achieve social success by observing and imitating others, creating an alternative persona, or escaping into the world of imagination through solitary fantasy play, reading fiction, or being with animals rather than peers. These mechanisms may mask the characteristics of Asperger’s for some time, such that the child tends to slip through the diagnostic net during the primary or elementary school years.

A girl may appear to have reciprocal conversations and use appropriate affect and gestures during an interaction. However, observation may determine that the child adopts a social role and practices a social “script”, basing her persona on the characteristics of someone who would be reasonably socially skilled in the situation and using intellectual abilities rather than intuition to determine what to say or do. This can include, for example, matching voice and accents, adopting a hairstyle, gait, or style, making eye contact even though it causes discomfort, or controlling self-stims when in unaccepting company. This is a compensatory mechanism often (but not exclusively) used by girls with AS, who are thus able to express superficial social abilities that can be confusing to the diagnostician.

This can also include rehearsing before an event; self-reminders to sit up straight, to not pick at teeth or twirl hair, or the “Quiet hands,” “Look at me,” “Stop tapping” practice of filler statements. Much effort goes into this behaviour.

Another response to the difficulty of ‘reading’ social situations could be to seek social engagement actively, be conspicuously intrusive and intense, dominate the interaction, and be unaware of social conventions such as acknowledging personal space. There is an imbalance in social reciprocity.

Psychological costs may become apparent only in adolescents. It is emotionally exhausting to constantly observe and analyze social behaviour, trying not to make a social error or be perceived as different.

Adopting an alternative persona can also lead to confusion about self-identity and low self-esteem. Stress, strain, and exhaustion can result in the development of clinical depression. ASC may be subsequently identified.

Unfortunately, camouflaging is seriously exhausting and can take a serious toll on mental health, with depression and anxiety, to the point where masking is a risk marker for suicide. Camouflaging can prevent or seriously delay an autism diagnosis, further reinforcing the gender differences in diagnosis.

When a neurotypical person asks why they camouflage, they respond, “We are told that autistics are impaired, that we need fixing or to be cured. We are stigmatized, dehumanized, and marginalized. And you want to know why I disguise myself!”. It may be to avoid bullying. Many autistic people credit camouflaging for their social and vocational success, as they experience less stigma and marginalization in these spaces when their autistic traits are less pronounced.

A PERSON WITH AN EATING DISORDER MAY BE DISGUISING THEIR AUTISM.
Autistic females are present in higher numbers in eating disorder (ED) clinics. In the presence of a potentially debilitating physical condition, autistic traits may be overlooked or may not be prioritized. Females with ED and autistic traits tended to be erroneously labelled ‘resistant’ and ‘naughty’; many of these women knew their symptoms were not associated with the ED.

There is a significant overlap between autism and eating disorders (ED). The prevalence of ASC in persons diagnosed with anorexia nervosa is 30%. Patients with both anorexia nervosa and AS fail to respond to treatment as well, have worse adaptive functioning, and require more intensive and more prolonged treatment regimens. It is therefore critical to distinguish between those with and without AS to provide the most appropriate intervention regimen.

GENDER DIVERSITY AND SEXUAL ORIENTATION MAY DISGUISE THEIR ASC
When another condition is so observable, the AS may be less salient. Autistics are more likely than neurotypicals to be gender diverse, and gender diverse folks are more likely to be autistic than are cisgender people. In gender diverse children, the rate of ASC is approximately 37 times higher than would be expected in the general population. 22.5% of transgender adolescents and adults have a diagnosis of autism.

The transgender presentation may disguise the autism when a parent has a teenager who discloses or acts upon their identity as differing from the sex which was assigned at birth, which will probably garner the parent’s attention far more than the fact that the child is struggling socially. Furthermore, they would have a ‘perfect’ excuse for why they are struggling socially; the salient presentation will be thought to be responsible.

Just as eating disorders clinics may open the door to the identification of female autistics, so may gender identity clinics. Sexual orientation plays a role in identifying ‘would-be autistics’ as well. Only 30% of autistics claimed to be heterosexual in comparison to 70% of neurotypicals. Autistic females present with greater diversity in their sexuality than either their male autistic counterparts or neurotypical female peers; they are less likely to be heterosexual than either group. Hence, the most salient, or noticeable, presentation of a pre-adolescent, for example, may be an unexpected sexual orientation.
Gay men may specifically relate to the ‘female characteristics’ of autism. The characteristics of the male autistic phenotype may not resonate with them.

MOTOR
Girls’ motor coordination problems may not be so conspicuous on the playground. They are much less likely to play sports. The autistic child, especially if a girl, is expected to be picked last in any team competition.
The overall appearance is that of a clumsy person. Movement and coordination problems will be evident to the PE teacher when playing games that require ball skills. They are immature in catching, throwing, and kicking a ball.
One consequence is the child’s exclusion from some of the social games in the playground. The child may then avoid these activities or bravely attempt them. Still, they can be deliberately excluded because they are perceived as a liability, not an asset to the team, and they are less likely to improve by practicing.
Parents need to practice ball skills from an early age. Some children with AS have greater coordination and fluency when swimming, develop agility on a trampoline, acquire coordination in solitary sports such as golf and running, and enjoy riding. These children can be at a level above their peers.

ADULTS
In actual clinical practice, an astute clinician finds that the ratio of men to women adults is as low as 2 to 1. Adults with AS can gradually learn to read social cues and conventions, so the signs of deficits in social-emotional reciprocity may not be conspicuous during short interactions such as a diagnostic assessment.
The requirement in the DSM-5 that the symptoms cause clinically significant impairment has created an interesting new development, namely, in some instances, officially and mutually agreeing to remove the diagnosis of AS in some adolescents and adults. Some young adults, who had the classic, clear and conspicuous signs of AS in early childhood, achieve over decades a range of social abilities and improvements in behavior such that the diagnostic characteristics became sub-clinical, that is, the person no longer has clinically significant impairment in social, occupational, or other important areas of functioning. There may still be subtle signs, but when the diagnostic tests are re-administered, scores below the threshold to maintain the diagnosis are not achieved in about 10%.
With increasing maturity, adults are prepared to get help, especially when there have been long-term and unresolved problems with emotions, employment, and relationships. Another pathway is when a woman has a child with AS and recognizes that she has a similar character.

THE COST OF MISIDENTIFICATION, LATE IDENTIFICATION AND NO IDENTIFICATION
Given brain plasticity, the earlier the intervention occurs, the better. It is not as though these females avoid life struggles; they endure relationship as well as academic struggles in addition to the internalized problems of anxiety and depression, among others. They are misidentified, over-medicated and many are hospitalized for eating disorders. They experience both burnout and exhaustion; camouflaging is exhausting. Given the adoption of an alternate identity, they are left questioning what about them is authentic and what is the mask. Because they have learned to socialize superficially, they do not accurately read non-verbal or subtle verbal signals, making them vulnerable to sexual exploitation and abuse.

Autistic females are 13 times more likely to die by suicide than non-autistics.

The system is failing these females. By not being accurately diagnosed, they do not receive autism-specific intervention or supports that could enhance their well-being and quality of life. We need to do better. Autistic females have been overlooked not just by society but by science.

RECOMMENDATIONS
Professional development for health care professionals and educators is critical. They all need to be trained on the various presentations of autism, including the intersection of gender and age.

Clinics need to be broad in their scope. Child development clinics must be sensitive to the potential for ASC across all genders, including those presenting diversely. Eating Disorders Clinics and Gender Diversity Clinics need to be sensitized to the potential for ASC in those presenting with both ED and SGM, respectively.

Diagnostic methods need to be revamped and adjusted. Observational methods are contraindicated with the prevalence of masking. It is imperative to employ diagnostic tools and questionnaires that accurately measure traits in females and non-binary individuals. Some instruments that can be of assistance are:
Q-ASC (Questionnaire for ASC)
CAT-Q (Camouflaging Autistic Traits Questionnaire)
GABS (Gendered Autism Behavioural Scale)
ASSQ-Rev (Autism Spectrum Screening Questionnaire)
Researchers need to recruit females and other non-cis-male study participants actively. They can also seek guidance from adult female autistics on how to recruit more female, trans, gender diverse, and non-binary study participants.

Autism; it’s not just for males anymore.

References
1. Autism: It’s Not Just for Males Anymore – Glenis Benson, PhD
https://aidecanada.ca/resources/learn/asd-id-core-knowledge/autism-it s-not-just-for-males-anymore
2. This is How Autism Looks Different in Girls and Women by Rachel Fairbank – November 22, 2024 National Geographic Magazine