Traumatic brain injury: why sex and gender differences matter

We often say that no two brain injuries are the same.

It is one of the first things people learn about traumatic brain injury (TBI), and for good reason. The same type of injury can affect two people very differently.

But there is something I keep coming back to in my work. If we accept that brain injury is so individual, why has so much of our understanding of it historically been based on men?

For a long time, the male experience was effectively the default in medical research. We are beginning to understand much more about the differences sex and gender can make to brain injury, from the likelihood of being injured in the first place to symptoms, recovery, hormones, caring responsibilities and the way someone’s difficulties are recognised by other people.

As a solicitor working with people and families affected by brain injury, I regularly see how difficult the less visible consequences of an injury can be to explain. Fatigue, changes in concentration, emotional regulation, memory or confidence cannot necessarily be seen from the outside.

So, for me, looking properly at sex and gender is not about making assumptions about somebody because they are a woman or a man. Quite the opposite. It is about asking better questions and understanding the individual in front of us.

Before going further, there is an important distinction. Sex relates to biological differences, including anatomy, hormones and physiology. Gender encompasses socially constructed roles, expectations and identity. In real life, of course, those things can overlap. In the context of brain injury, both can matter.

Historically, women were often excluded or under-represented in medical research. Hormonal cycles, pregnancy, breastfeeding and reproductive health could be regarded as complicating factors.

It may have made studies simpler to conduct, but it left a significant gap in our knowledge. Findings based mainly on men were then applied much more widely, often without enough evidence about whether women might experience different symptoms, risks, treatment effects or patterns of recovery.

That has changed considerably in clinical research, and there is now much greater recognition of the need to consider sex when studies are designed, analysed and reported.

But simply including women in a study does not necessarily give us the answers we need. If everybody’s results are grouped together, differences between women and men can disappear into the average. Where possible, looking separately at the data can tell us far more.

At first sight, the statistics suggest that head injury is predominantly a male problem.

Headway’s figures for 2023–24 record 123,969 hospital admissions for head injury in the UK, equivalent to one admission every four minutes. Men were 1.5 times more likely than women to be admitted.

That reflects some well-known differences in exposure to risk, including road traffic collisions, falls, assaults and sport.

But admission figures only tell us about people who reach hospital and whose injuries are recognised.

A mild traumatic brain injury or concussion may never result in an admission. Nor will every person who has suffered a brain injury seek medical help.

Domestic abuse is an important example. Someone may have suffered repeated blows to the head or injury associated with strangulation without ever describing what happened to them as a brain injury. Their immediate concern may quite understandably be safety. Trauma, stigma or control by an abuser may make seeking help still harder.

Symptoms can then be attributed to anxiety, stress or emotional distress when brain injury may also be part of the picture.

That is one of the reasons I think we need to be cautious about what apparently straightforward statistics are really telling us.

There isn’t a simple answer to that, and the research is still developing.

A 2026 systematic review by Arachchi and colleagues looked at 41 studies involving 12,382 adults with mild traumatic brain injury or concussion across sport, military, domestic violence and civilian settings.

Some differences did emerge. Women reported more symptoms overall and more pain. Some measures also suggested a longer recovery, alongside greater effects on thinking speed, balance and vision.

The brain imaging findings were different too. Women showed more extensive changes in white matter connections, while men showed greater reductions in cerebral blood flow.

Of course, that doesn’t mean a woman with concussion will necessarily recover more slowly than a man. Brain injury is far too individual for that. But it does make me wary of using broad averages to tell someone what their recovery ought to look like.

Hormones are another part of this that can easily be overlooked.

A brain injury can disrupt the communication between the brain and the body’s hormone system. The consequences are not always obvious. Fatigue, low mood, cognitive problems, sleep disturbance, changes in weight or sexual dysfunction may simply be regarded as part and parcel of living with a brain injury.

Sometimes they may be. But sometimes there may be an endocrine problem that warrants investigation.

For women, periods, menopause, fertility treatment, pregnancy and recovery after childbirth may all interact with symptoms following TBI.

For men, testosterone deficiency and sexual dysfunction may be relevant but may not readily be volunteered.

And we should not assume everybody’s circumstances fit neatly into either category. For transgender people, for example, endocrine changes following TBI may interact with gender-affirming hormone therapy, while changes involving mood, cognition, sleep, sexual function or body image may carry their own particular significance.

These can be difficult subjects to discuss. But if nobody asks, an important part of someone’s injury may never be properly understood.

Biology is only one part of this.

Gender can affect what recovery actually looks like at home.

Women are still more likely than men to provide unpaid care. Census 2021 data recorded around five million unpaid carers aged five and over in England and Wales, with women more likely than men to provide that care.

That matters after a brain injury.

Imagine that the person who has been injured is also the person who normally gets the children ready in the morning, keeps track of appointments, checks on an elderly parent, cooks, shops and quietly holds much of family life together.

Where is the space for that person to recover?

Resting, pacing activity, attending rehabilitation appointments or simply admitting that you need help may be much harder when other people are accustomed to relying on you.

I think this is an area where we can sometimes underestimate the true impact of an injury. What somebody was doing before their accident may never have appeared on a payslip, but losing the ability to do it can have profound consequences for the whole family.

Sport provides another example of why the male experience should not automatically be treated as the benchmark.

There has rightly been enormous attention in recent years on the possible long-term effects of repeated head injury in men’s professional sport.

The picture for women and girls has received rather less attention.

A large US study of teenage footballers, involving Professor Willie Stewart at the University of Glasgow, found that girls had 1.88 times the documented concussion risk of boys. They were also less likely to be removed from play immediately and took longer, on average, to return to play.

That raises an obvious question.

If one group appears to be at greater risk, should our approach to concussion be designed around that higher level of risk rather than around what has historically happened in men’s sport?

The message behind initiatives such as “If in doubt, sit them out” is refreshingly simple: take concussion seriously and remove the person from further risk.

There is still work to do, particularly around awareness in grassroots and women’s sport, but that basic principle is an important one.

One organisation that has done a great deal to bring attention to these issues is Pink Concussions, which focuses on brain injury in women and girls across sport, domestic violence, accidents and military service.

Its combination of research, education, advocacy and lived experience has helped challenge the idea that evidence gathered predominantly from men can simply be transferred to women.

I was also pleased to see these issues being discussed when I attended an event at the Houses of Parliament in September 2026, hosted by Dr Mohamed Sakel, Medical Director at Frenchay Brain Injury Rehabilitation Centre, and supported by the United Kingdom Acquired Brain Injury Forum (UKABIF).

What particularly interested me was that intersectionality formed part of the discussion. Brain injury does not happen to somebody in isolation from everything else about their life.

Members of Parliament were there too, which mattered. If we want research priorities, rehabilitation services and wider understanding of brain injury to change, these conversations need to reach the people in a position to influence policy.

But the issues are not confined to research or healthcare.

They matter in my own profession too.

For me, this is where much of the research becomes very practical.

A brain injury claim should tell us what has happened to the person, not simply catalogue a diagnosis and a list of symptoms.

Sex and gender can form part of that story.

A client may not think to mention changes to their periods, libido or fertility plans. They may feel embarrassed talking about bladder or bowel problems. Changes in intimate relationships can be particularly difficult to disclose.

Unless we explain why we are asking about those things, we may never hear about them.

The same is true of caring responsibilities. If somebody previously provided a large amount of unpaid care or quietly performed most of the work involved in running a household, losing that capacity needs to be identified. It may be every bit as real a consequence of their injury as a loss of earnings.

This is why detailed evidence about life before and after an injury matters so much.

Medical appointments give us one view of somebody. Family members, friends, colleagues and support workers may see something quite different: the fatigue later in the day, the loss of confidence, difficulty organising family life, changes in judgement or emotions, or simply how much more effort ordinary things now require.

I also think we have to remain alert to our own assumptions.

A woman describing persistent symptoms following a mild TBI should not simply be written off as anxious or as over-reporting what she is experiencing.

Equally, a man who says very little about emotional, cognitive or sexual difficulties may not be unaffected. He may simply find them difficult to discuss.

People of any gender may minimise what they are going through because they want to get back to normal, protect their family, keep their job or avoid being treated differently.

The only way to understand that properly is to ask, listen and keep asking the questions that matter.

There is encouraging progress. The gaps left by research based predominantly on men are increasingly being recognised. But simply including more women in studies is only part of the answer. We also need to look carefully at whether men and women are experiencing brain injury differently, rather than assuming that an average result tells us everything we need to know.

For clinicians, rehabilitation professionals and lawyers, that means looking beyond the mechanism of somebody’s injury.

Who were they before it happened? What did other people rely on them for? What has changed physically, cognitively and emotionally? What are they reluctant to tell us?

We often say that no two brain injuries are the same. If we really mean that, we need to make sure we are looking at the person in front of us as an individual, rather than measuring them against a default that may never have reflected them in the first place.