Beyond Gender-Affirming Rhetoric: Scrutinising Population-Level Data

A large 2025 study from the US has received relatively little attention despite analysing long-term data from over 107,000 medically transitioned people.

Update: I should state upfront that I am not only a psychologist but a mother of a young adult TID. I never went looking for this issue. It came to me, seemingly out of nowhere, and flipped me on my head. I love my child more than anything, and this has come between us (as it so often does). Like other parents and clinicians, I was not allowed a voice. So here I am in 2026, channelling my anguish into regularly checking the research, listening, talking, and reading all I can in my desire to make sense of something that has blindsided so many parents and families. I heard about the Lewis paper (summarised in this essay) in late 2025. Finding very little in Google News searches recently about this data, I thought it time to try and get it out there.

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Patient care should always be driven by rigorous, verified data rather than short-term clinical trends. This standard is especially vital for irreversible medical procedures, which must be backed by ironclad evidence or suspended until clear data emerges. We only need to look at historical tragedies like thalidomide or prefrontal lobotomies to remember what happens when medical enthusiasm outpaces evidence

This principle should not be controversial. It is the foundation of good healthcare and the Hippocratic Oath. When treatment involves major physical changes to multiple body systems, lifelong consequences, and complex psychological factors, patients, clinicians, and policymakers need reliable datasets about benefits and risks. They need to know not only whether an intervention helps some people long-term, but who benefits, who does not, what risks exist and when, and whether those risks are being thoroughly interrogated before treatment.

The debate surrounding gender-affirming care (GAC), including gender-affirming surgery (GAS), has often been framed as a conflict between two sides: necessary, life-changing medical treatment supported by studies involving relatively small numbers of patients recruited through clinics, versus concerns about longer-term risks, with critics pointing to weak long-term evidence and poor study design. Even though the popular media have shied away from recent systematic reviews - including the 2024 Cass Review – it is inarguable that the evidence supporting widespread use of puberty blockers, cross-sex hormones, and GAS is considerably weaker than advocates have previously claimed, and that harms have not received sufficient attention.

Even as activists purport: “Gender-affirming care saves lives” I believe we can bypass this debate with one simple question: Is the evidence base sufficient to justify current levels of certainty expressed by GAC advocates?

I argue that it is not.

A recent large-scale longitudinal study

A large study published in 2025 by Lewis et al., Examining Gender-Specific Mental Health Risks After Gender-Affirming Surgery: A National Database Study, has received relatively little attention despite analysing data from more than 107,000 people diagnosed with gender dysphoria between 2014 and 2024. The researchers created several matched cohorts, comparing patients who underwent GAS with those who did not. To improve comparability, participants were matched by age, race, and ethnicity using propensity score matching.

This study deserves wide-spread attention for two reasons.

First, it is one of the largest attempts to examine mental health outcomes following GAS using real-world healthcare data.

Second, unlike previous studies that relied on self-reported satisfaction surveys (”Are you pleased with your decision?”), the researchers examined objective mental health outcomes based on actual clinical diagnoses recorded in medical records.

The findings revealed consistent patterns. Among individuals recorded as male in the medical records who were diagnosed with gender dysphoria, those who underwent surgery experienced more than double the rate of depression compared with those who did not (25.4% vs. 11.5%), and nearly five times the rate of anxiety (12.8% vs. 2.6%). Suicidal ideation and substance use disorders were also more common among the surgical group.

A similar pattern appeared among patients recorded as female. Those who underwent surgery were more likely to receive diagnoses of depression (22.9% vs. 14.6%), anxiety (10.5% vs. 7.1%), suicidal ideation (19.8% vs. 8.4%), and substance use disorders (19.3% vs. 7.1%) compared with those people who did not go ahead with surgery.

Now let me humanise these stats. While writing this essay, I saw this Julie Bindel interview with a trans-identified man, Vivenne Taylor, recently released from jail after stalking his gender-affirming surgeon Dr Tina Rashid for four years post surgery, electronically and in person, including emails with threats of battery and sexual assault. Vivienne is a telling case study - as you will see if you watch this interview at London Pride - highlighting the complications, both medical and psychological, that can happen following GAS.

{Side note: My psychologist brain saw a “Mother Phantasy” during that interview, an unconscious projection by Vivenne onto his female doctor of some deep yearning for a Mother who hurts but then heals, who offers abiding and unconditional love. I have no history about this individual, but suffice to say, my heart breaks for these vulnerable young adults, and I wonder how these surgeons sleep at night!}

The take-away from the Lewis study

Now back to the data. This study seriously undermines the primary justification for GAS - that these surgeries improve people’s mental health – showing that this claim is not supported by population-level evidence. It also adds to other population-based findings, including Bränström and Pachankis (2020) and Ruuska et al. (2024) which reported higher rates of psychiatric treatment (including antidepressant and anxiolytic prescriptions, as well as hospitalisation following suicide attempts) among transgender individuals who received GAC or underwent GAS than among those who did not.

Although the Lewis study does not settle every question and does not prove that surgery worsens life outcomes, it contributes an unusually large piece of evidence to a field where long-term data have been scarce. Its findings strongly suggest that GAS is associated with poorer mental health outcomes rather than measurable improvements.

If you watch the Pride interview with Vivienne Taylor and Julie Bindel, you will hear Vivenne say: “I am happy to be a trans-woman” and yet the life outcomes, objectives measures of life success, seem to indicate that GAS has not helped make a better life for this individual. This is consistent with decades of social psychology research showing how we convince ourselves we are happy with our choices to reduce mental discomfort or cognitive dissonance (a deeply human bias known as self-serving bias or sometimes post-purchase rationalisation).

Why the Lewis study matters

One of the greatest challenges in studying trends or long term outcomes after medical transition is long-term follow-up. Sometimes because clinics don’t do any at all. Sometimes because doing so is challenging.

Youth gender clinics in most countries contain major data gaps. The Tavistock Gender Identity Development Service (GIDS) in London conducted no systematic long-term follow-up of patients, while adult gender clinics in the UK have reportedly declined to share data with researchers (Cass, 2024). During the landmark UK High Court case brought by detransitioner Keira Bell, the absence of long-term clinical follow-up became part of the formal legal record. Even clinicians involved in establishing the service - including David Freedman* - described the lack of outcome data as “mind-boggling” and a “monumental scandal” (Barnes, 2023).

Most published GAC studies recruit participants through specialist clinics. Consequently, sample sizes are modest, follow-up periods relatively short, and participant attrition substantial. Loss-to-follow-up exceeding 60% is common (for example, van de Grift et al., 2018) even in smaller studies. Loss-to-follow-up is not merely a technical limitation. It is one of the central methodological challenges in this field. Researchers lose contact with people who leave treatment, relocate, or simply choose not to participate in later surveys. As a result, those who remain in studies are unlikely to represent everyone who underwent treatment. Researchers rarely know why people disappear or what their long-term outcomes were.

By contrast, the Lewis study drew upon a very large electronic health-record database, allowing researchers to examine population-level outcomes across more than 107,000 patients. Until its publication in 2025, evidence of this scale had been largely absent from the literature.

The voices missing from the data: detransition, lawsuits, and unanswered questions

The importance of long-term evidence becomes even clearer when considering people who later reconsider, discontinue, or reverse their transition.

In recent years, detransitioners have become increasingly visible through personal accounts, online communities such as r/detrans, advocacy organisations including Genspect, Detransitioner Network UK, and SEGM, and an increasing number of medical malpractice lawsuits alleging inadequate assessment, insufficient exploration of underlying psychological issues, and inadequate discussion of risks and outcomes.

These accounts should be taken seriously. And they should be interpreted carefully.

Just as proponents of GAC should not rely solely on small studies or personal testimonies to justify treatment, critics should recognise that individual accounts cannot substitute for population-level evidence. Nevertheless, they raise questions that any responsible healthcare system should want to answer:

• Did each patient receive a thorough assessment of how their gender dysphoria started and developed before irreversible interventions?

• Were alternative explanations for distress adequately explored?

• Were realistic expectations about what medical transition could and could not achieve clearly discussed?

• Were patients prepared for the possibility that their understanding of themselves or their feelings might change over time?

These are not political questions. They are standard clinical questions asked whenever medicine involves interventions with significant and irreversible consequences.

Decent healthcare systems actively discuss and investigate complications, dissatisfaction, regret, and changing outcomes over time.

It is important to add that clinicians, researchers and policy-makers should neither suppress discussions or findings about these issues, as occurred following the publication of a paper by Jason Watson** reviewing 30+ years of evidence. Watson’s paper titled: “What are the facts regarding trans youth and suicide? Taking a second look at the trans youth suicide narrative published in the Australian Nursing & Midwifery Journal(July–September 2026) was quickly retracted following protests from transgender activists who argued that Watson was promoting “damaging and harmful opinions” and “causing distress” (Accurate Research Beats Ideology, 2026)

The question of psychological assessment

Many members of the public assume that hormones and surgery require months or years of psychological assessment. Yet there are thousands of reports from young people describing access to hormones or surgery after only one or two appointments (Hakeem, 2023). Gender-related distress frequently coexists with trauma, neuro-developmental differences, body image concerns, interpersonal difficulties, and broader identity struggles. As I have argued elsewhere, understanding this complexityshould be central to patient care.

This reflects a broader medical principle: treating symptoms without fully understanding their underlying causes often leads to poorer outcomes. When interventions involve permanent physical changes, comprehensive assessment should be regarded as a safeguard rather than an obstacle.

Detransition and the challenge of measuring “rare” outcomes

GAC advocates claim regret is rare, stating that it is less than 1%. In reality, no evidence exists to reliably make this or similar claims. Detransition is especially difficult to study because it requires long-term follow-up, suffers from high rates of participant attrition, and exists within a research environment where clinicians and researchers have experienced significant professional backlash for publishing findings that challenge the dominant GAC model. Researchers including Lisa Littman, Kenneth Zucker, and Michael Biggs have all have faced severe professional backlash, public denunciation, and career sanctions. Here in Australia, Dr Jillian Spencer faced years of controversy and job loss after publicly raising concerns.

These professional consequences discourage researchers and clinicians from investigating detransition and related questions. Outside academic research, online communities such as r/detrans have highlighted concerns regarding assessment, expectations, regret, and follow-up care. A new AI project (https://detrans.ai/en), launched in 2025, analyses qualitative data drawn from tens of thousands of posts from the detrans subreddit, which had more than 63,000 members as of July 2026.

Although these communities cannot establish prevalence, they provide valuable qualitative data and identify important questions worthy of systematic investigation. Ultimately, a mature healthcare system should seek accurate information about every possible outcome:

• Who will persist?

• Who will desist?

• Who will benefit?

• Who will be harmed?

• Who experiences complications?

• Why?

Why the Lewis study represents an important turning point

The significance of the Lewis study should not be understated.

Although it cannot determine whether surgery caused the mental health outcomes observed, nor capture every individual experience, it represents something that has been notably scarce in this field: very large-scale, longitudinal evidence. When findings challenge existing assumptions, the appropriate response is not dismissal but further investigation.

If GAS provides benefits for many patients, research should demonstrate those benefits. If there are risks, missed opportunities for psychological intervention, inadequate assessment processes, or groups of patients whose needs are not being met, robust research should identify those as well.

Patients deserve accurate information. Clinicians deserve high-quality evidence. Medicine deserves the courage to examine difficult questions. The future of healthcare in this field should not depend on defending assumptions. It should depend on better evidence, longer follow-up, deeper psychological understanding, and a commitment to learning from every patient experience, including those that challenge prevailing narratives.

References

Accurate research beats ideology. (2026, July 15). The Australian. theaustralian.com.au

Barnes, H. (2023, March 19). No one kept data on Tavistock children and it’s a monumental scandal. The Times. https://www.thetimes.com/uk/healthcare/article/no-one-kept-data-on-tavistock-children-its-a-monumental-scandal-z766jbmvm

Bränström, R., & Pachankis, J. E. (2020). Correction to Bränström and Pachankis. The American Journal of Psychiatry, 177(8), 734.

Cass, H. (2024). The Cass Review: Independent review of gender identity services for children and young people: Final report. NHS England. independent-review.uk

Hakeem, A. (2023). Detrans: When transition is not the solution. Independently published

Lewis, J. E., et al. (2025). Examining gender-specific mental health risks after gender-affirming surgery: A national database study. The Journal of Sexual Medicine, 22(4), 645–651. https://doi.org/10.1093/jsxmed/qdaf026

r/detrans. (n.d.). Home [Reddit]. Retrieved July 26, 2026, from reddit.com

Ruuska, S.-M., Tuisku, K., Holttinen, T., & Kaltiala, R. (2024). All-cause and suicide mortalities among adolescents and young adults who contacted specialised gender identity services in Finland in 1996–2019: A register study. BMJ Mental Health, 27(1). https://doi.org/10.1136/bmjment-2023-300940

van de Grift, T. C., Elaut, G., Cerwenka, S. C., Cohen-Kettenis, P. T., De Cuypere, G., Richter-Appelt, H., & Kreukels, B. P. C. (2018). Effects of medical interventions on gender dysphoria and body image: A follow-up study. International Journal of Impotence Research, 30(4), 175–183.

* David Freedman helped audit the first 124 patients seen by the Tavistock GIDS following its establishment in 1989. Decades later, he discovered that this early audit remained the only long-term evaluation the clinic had ever undertaken (Barnes, 2023).

** Jason Watson reviewed 30–40 years of historical and longitudinal evidence from the Netherlands, Sweden, Denmark, and Finland. His paper challenged the commonly repeated claim that youth suicide risk increases dramatically when gender-affirming medical treatments such as puberty blockers or cross-sex hormones are withheld. His analysis also aligned with conclusions reached by the UK’s independent Cass Review and suicide prevention expert Professor Louis Appleby.

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