Autism Spectrum Disorder (ASD) has long been perceived as a predominantly male condition, leading to the underdiagnosis and misdiagnosis of thousands of women and girls. This gender bias has contributed to a significant gap in understanding the true nature of autism, particularly its manifestation in females. As diagnostic criteria and research frameworks are increasingly scrutinized and revised, the picture that emerges is of a much more complex and nuanced condition than previously thought. In this post, we will explore the reasons behind the underdiagnosis of autism in women, how it presents differently in girls, and why recognizing these differences is crucial to improving mental health outcomes.

Autism gender bias: A historical oversight

Historically, autism has been viewed through a predominantly male lens, with research studies and diagnostic criteria being heavily skewed toward the experiences of boys and men. Early studies on autism typically involved male participants in overwhelming numbers. For example, participants in brain imaging studies of autism outnumber females by a ratio of 8:1, and some earlier studies did not include female participants at all. As a result, our understanding of autism is largely shaped by male presentations of the condition, which has led to a systematic failure to recognize how autism manifests in women and girls.

This historical bias has had far-reaching consequences. For years, autism spectrum disorders, especially those without intellectual impairments (such as Asperger's syndrome), were thought to affect males at a rate of approximately 10 to 1. However, more recent research has begun to challenge this assumption. By employing active screening methods rather than relying solely on clinical records, researchers have revised the gender ratio to closer to 3:1. Leading neuroscientists, such as Professor Francesca Happé, suggest that as diagnostic tools become better tailored to girls and women, the ratio could potentially fall even further, possibly to 2:1.

This shift is significant. If the real ratio is indeed closer to 3:1 or 2:1, it would mean that up to 200,000 women and girls in the UK alone could be on the autism spectrum, but have been missed by the current diagnostic framework. These women are likely to have gone through life struggling with social interactions, communication difficulties, and mental health challenges, without understanding why they feel different.

Why are girls being missed?

One of the key reasons for the underdiagnosis of girls with autism lies in the way it manifests differently in females compared to males. Autism is often characterized by persistent difficulties in social interaction and communication, as well as restricted, repetitive patterns of behaviour or interests. However, the way these traits are expressed can differ between genders.

Girls and women with autism tend to be more adept at "masking" their autistic traits. This phenomenon, often referred to as "social camouflaging," involves consciously or subconsciously mimicking the behaviour of their neurotypical peers in order to fit in. For instance, many autistic girls will identify a popular or socially adept girl in their class and study her behaviour, speech patterns, and social cues, imitating them to avoid standing out. This masking can be incredibly exhausting and may lead to burnout and mental health issues later in life.

The interests of autistic girls may also appear more socially acceptable than those of boys. While a boy with autism might display a deep, narrow interest in topics like electricity pylons or train schedules, a girl might become similarly fixated on subjects that seem more typical for her age, such as animals, boy bands, or fashion. While the intensity and persistence of these interests may still be unusual, they are often dismissed as normal phases of growing up, further obscuring the potential diagnosis of autism.

Professor Happé notes that traditional diagnostic tools are not sufficiently sensitive to these gender differences. Because the early diagnostic criteria were developed primarily with boys in mind, many clinicians still fail to recognize the more subtle presentations of autism in girls. This has resulted in widespread misdiagnosis, with many autistic girls being incorrectly labelled as having anxiety disorders, depression, or even eating disorders, without the underlying cause being identified.

The impact of misdiagnosis and undiagnosis

The failure to diagnose autism in girls and women has serious mental health consequences. Research indicates that many undiagnosed women experience secondary mental health issues such as anxiety, depression, and even self-harm. Studies have shown that the prolonged stress of trying to navigate a world that does not recognize or accommodate their differences can take a significant toll on their wellbeing.

For example, a study conducted in 2016 found that 23% of women hospitalized for anorexia met the diagnostic criteria for autism. This suggests that in some cases, the social and communication difficulties associated with autism may predate the onset of eating disorders, but clinicians may not be attuned to this connection. If autism is not considered when treating these women, clinicians might focus solely on managing the eating disorder without addressing the underlying social difficulties that contribute to the patient's distress.

This issue is further compounded by the societal stereotypes around autism. Media portrayals, such as the well-known movie “Rain Man”, have almost exclusively depicted male characters, reinforcing the belief that autism is a "male" condition. As a result, parents, teachers, and even healthcare professionals may be less likely to consider autism as a possibility when they encounter a girl or woman struggling with social or communication challenges. Instead, these individuals are more often diagnosed with conditions such as borderline personality disorder, bipolar disorder, or generalized anxiety disorder, without the real underlying issue being recognized.

Why diagnosis matters

Receiving an autism diagnosis can be a transformative experience for women and girls. It provides an explanation for why they have felt different for so long, and helps them to find communities of others who share their experiences. It also enables them to access support services that can help them manage their symptoms and navigate the challenges of daily life.

Hannah Belcher, an autism researcher at Anglia Ruskin University, who was diagnosed in adulthood, reflects on how an earlier diagnosis could have helped her cope with the mental health difficulties she experienced as a child. "I had anxiety as a child and stopped going to school at 14 because I was struggling to cope," she explains. "It was only when I was 23 that I saw an art therapist who suggested I was possibly autistic. I am certain I would have gained more support around my anxiety as a child and would have suffered from less mental health difficulties had I had the diagnosis earlier."

For many women, an autism diagnosis brings a sense of relief and validation. Understanding their own neurodivergence allows them to stop masking and accept their authentic selves. In turn, this can improve their self-esteem, relationships, and overall quality of life.

Embracing differences in processing

The growing recognition of gender differences in autism is encouraging, but there is still much work to be done. Diagnostic criteria need to be updated to reflect the unique ways autism can manifest in women and girls. Clinicians, teachers, and parents must be educated on the signs of autism in females to ensure that no girl or woman goes undiagnosed.

As our understanding of autism continues to evolve, it is crucial that we challenge the longstanding biases and assumptions that have shaped research and clinical practice. Only by acknowledging and addressing these differences can we begin to provide better support for the thousands of women and girls who are currently being overlooked. It is time to shift the narrative, ensuring that autism is recognized not as a male condition, but as a human condition—one that affects people of all genders.