Signs of Autism in Girls: Why It’s Often Missed (and What to Look For)

At Insight, we support children, young people and families through autism assessment and follow-up care.

It’s important to say from the outset that autism does not belong to one gender. Some boys mask. Some girls present more overtly. Some children don’t fit neatly into either pattern.

But increasingly, we are recognising that some autistic presentations — often more internalised, more socially camouflaged, and more effortful — are easier to miss, particularly in girls and young people who feel a strong need to fit in.

For many years, autism has been described as affecting boys far more than girls, often quoted as around a 4:1 ratio.

More recent research is beginning to challenge that picture. A large population study published in The BMJ, following over 2.7 million people, suggests that while boys are more likely to be diagnosed in childhood, girls are often identified later, with diagnosis rates becoming much closer by early adulthood.

This raises important questions about how autism presents, how it is recognised, and who might be overlooked.

In clinical practice, this is something many of us have seen for a long time.

Girls were often referred to services not because someone suspected autism, but because of anxiety, low mood, school avoidance, or difficulties with friendships.

It was only through taking time to explore these experiences more fully and by looking at patterns over time, and understanding how hard a person was working to cope that a different picture sometimes began to emerge.

Not always. But often enough to raise important questions. This article explores those questions. It looks at why some presentations of autism can be harder to recognise, what that might look like in day-to-day life, and how families can begin to make sense of patterns that don’t always fit the stereotypes.

Why some presentations of autism are easier to miss

Part of the answer lies in how autism has historically been understood and described.

Diagnostic frameworks, including those used in the UK, are based on criteria set out in manuals such as the DSM-5. These criteria provide a shared language and help ensure consistency across services.

But they are shaped by the research available at the time they were developed — much of which focused on boys.

As a result, the examples we often associate with autism, including more visible social differences or overt behaviours, do not always capture the full range of how autism can present.

Masking and internalised presentations

Some children, particularly those who are socially aware or motivated to fit in, develop ways of adapting to their environment.

This might include:

• carefully observing and copying peers

• rehearsing what to say in conversations

• following rules closely to avoid standing out

• suppressing behaviours that might draw attention

Over time, these strategies can become so well practised that difficulties are less visible. From the outside, a child may appear to be coping. Internally, it can feel effortful, confusing, or exhausting.

When differences are less visible

In these more internalised presentations, differences may show up in ways that are easier to attribute to other things.

For example:

• anxiety

• low mood

• perfectionism

• school avoidance

• friendship difficulties that are hard to define

These are often the reasons families first seek support.

And while these experiences in themselves are very real, they can sometimes be understood more fully when we also consider whether a young person may be navigating the world with an underlying neurodevelopmental difference.

The role (and limits) of assessment tools

Assessment tools help clinicians gather information in a structured, evidence-based way.

Tools such as the ADOS-2 and developmental interviews are widely used and considered best practice.

However, they are not perfect.

They are designed to identify patterns traditionally associated with autism, which means more subtle or well-masked presentations may not always be immediately apparent.

This is why assessment should never rely on one tool alone.

Clinical judgement matters

A meaningful assessment brings together multiple sources of information:

• developmental history

• observations across settings

• input from parents and schools

• and the young person’s own experience

Just as importantly, it requires time, curiosity, and clinical experience.

At Insight, we use recognised tools as part of best practice, but we interpret them within the context of the whole child, by considering what is visible, what is less visible, and what it may take for that child to manage in different environments.

For many families, it is this process of understanding that helps things begin to make sense.

What this can look like in day-to-day life

Often, it is not one behaviour, but a pattern over time.

You might notice:

A difference between environments: A child who appears to cope well in school, but is overwhelmed at home.

They may:

• hold things together during the day

• become tearful, angry or withdrawn afterwards

• need significant time alone to recover

Social relationships that feel effortful: A child may want (and have) friendships, but:

• find it hard to keep them going

• feel unsure of social rules

• rely on one close friendship at a time

• come home feeling confused or hurt without being able to explain why

Sometimes, they learn to “blend in” socially — but this can take a lot of energy.

Strong interests that don’t stand out immediately

Interests may be:

• intense, or with an unexpected level of expertise but socially typical

• pursued with depth and focus•

used as a way to feel calm or in control

Because the content feels age-appropriate, the intensity can be overlooked.

A tendency towards perfectionism or rule-following

Some children:

• are very aware of expectations

• become anxious about getting things wrong

• follow rules closely, sometimes rigidly

• feel distressed when things are unpredictable

Sensory differences that are managed quietly

For example:

• avoiding certain clothing - easier to do when you choose your own or have a particular 'style'

• sensitivity to noise or busy environments

• becoming overwhelmed in ways that aren’t always obvious

Emotional responses that build up over time

You might notice:

• big reactions that seem to come “out of nowhere”

• difficulty recovering once upset

• a sense that things have been building under the surface

For some of the adults we work with, these patterns only begin to make sense much later. It’s not uncommon to hear: “I wish I’d understood this about myself sooner.” Many people describe years of trying to work things out — replaying conversations, developing internal “rules”, or mentally mapping how to respond.

From the outside, this can look like coping well. On the inside, it can feel effortful and exhausting.

Autism, anxiety, or both?

Many children described in this way are first understood as anxious. And often, they are.

But sometimes anxiety develops in response to a world that feels unpredictable or difficult to interpret.

Understanding whether anxiety sits alongside autism, rather than instead of it, can change the kind of support that is most helpful.

Trusting your sense as a parent

One of the things we hear most often from parents is: “I can’t quite explain it, but something doesn’t feel easy for them.”

That sense is important.

You don’t need to have all the answers. Often, it is patterns over time rather than one specific behaviour that tell us the most.

When might an assessment be helpful?

You might consider exploring an assessment if:

• your child seems to be working very hard to cope

• there is a noticeable difference between settings

• anxiety or emotional overwhelm is increasing

• their needs don’t feel fully understood

How we approach autism assessment at Insight

At Insight, our assessments are grounded in a neuroaffirmative and strengths-based approach.

We recognise that autism can present in many different ways, including those that are more subtle or internalised. Our assessments aim to understand the whole child, not just what is immediately visible.

We use recognised assessment tools alongside detailed developmental histories and input from multiple settings. Just as importantly, we take time to think carefully about what the information means for that individual child.

Finally, it’s also important to remember that support doesn’t have to wait for a diagnosis. Holding neurodiversity in mind when thinking about next steps can be helpful in itself. If you’d like to talk things through, we’d be very happy to hear from you.