BDZ NEWS HEALTH / SOCIETY. Finnish Study Finds Mental Health Treatment Remained High After Medical Gender Reassignment in Young People

A nationwide study followed more than 2,000 young people referred to Finland's gender identity services and found substantial psychiatric treatment needs before and after medical intervention. The findings are significant, but they do not establish that the treatments caused the increase.

By BDZ News Desk

Published: September 21, 2026

A large Finnish study is drawing attention to a difficult question surrounding medical treatment for young people experiencing gender dysphoria:

What happens to their mental health afterward?

Researchers examined nationwide health-register data involving 2,083 people under age 23 who were referred to Finland's specialized gender identity services between 1996 and 2019.

They compared those patients with 16,643 matched controls from the general population. SOURCE 

The results were striking.

Among young people in the study who underwent what researchers classified as medical gender reassignment, the proportion receiving specialist psychiatric treatment increased from 9.8% before treatment to 60.7% during follow-up among those undergoing feminizing treatment.

Among those undergoing masculinizing treatment, the figure increased from 21.6% to 54.5%. SOURCE

The researchers' conclusion was direct:

“Psychiatric needs do not subside after medical gender reassignment.” SOURCE

But understanding what those numbers mean requires looking beyond the headline.

Mental Health Problems Often Came First

The study did not begin with a group of otherwise psychiatrically healthy young people who developed mental-health problems only after treatment.

Psychiatric treatment needs were already substantially higher among young people referred to Finland's gender clinics.

Across the entire gender-referred group, 45.7% had received specialist psychiatric treatment before referral, compared with 15% among matched controls.

At least two years after referral, those figures were 61.7% among the gender-referred group and 14.6% among controls. SOURCE 

The difference became particularly pronounced among people entering gender services during the more recent period examined by researchers.

Among those referred after 2010, 47.9% had received specialist psychiatric treatment before their gender-clinic referral, compared with 15.3% of matched controls. At least two years afterward, the figures were 61.3% and 14.2%, respectively. SOURCE 

That suggests many patients were dealing with significant mental-health difficulties before medical gender treatment entered the picture.

After researchers adjusted for previous psychiatric treatment, gender-referred young people still had substantially higher subsequent psychiatric-treatment rates than controls. The study reported hazard ratios approximately three times those of female controls and five times those of male controls. SOURCE 

What Did Researchers Count as “Psychiatric Morbidity”?

This is an important distinction.

The study's primary measure of severe psychiatric morbidity was based on the need for specialist-level psychiatric treatment.

That is not exactly the same thing as measuring whether someone's depression, anxiety or other psychiatric symptoms became objectively more severe.

Researchers who subsequently published a methodological critique in Acta Paediatrica argued that increased use of psychiatric services should not automatically be interpreted as deteriorating mental health. Someone receiving more psychiatric care may be experiencing greater problems, but healthcare utilization and symptom severity are not interchangeable measurements. SOURCE

Critics also noted that the study grouped different medical interventions together, including hormonal and surgical interventions, rather than providing separate outcome estimates for each treatment type. SOURCE

That matters when claims about the study spread online.

Calling all of the treatments examined simply “sex-alteration procedures,” for example, obscures what researchers actually studied.

The Study Does Not Prove Treatment Caused the Increase

This may be the most important sentence in the story:

The study found an association. It did not establish that medical gender reassignment caused psychiatric illness, but we must also mention that it does not disprove it either.

The research was observational.

Patients were not randomly assigned to receive treatment.

And the young people receiving medical interventions may have differed in important ways from those who did not.

A methodological critique published in the same journal praised the Finnish study's nationwide sample, matched controls, long observation period and lack of loss to follow-up, while warning against causal interpretations of its findings SOURCE

The critics specifically raised the problem of confounding by indication.

In plain English, the people receiving treatment may already be different from the people who do not receive it in ways that also affect their future mental health.

The study attempted to account for previous psychiatric treatment statistically, but the critics argued that treating prior psychiatric care as a relatively simple variable may not fully capture differences in severity, duration and complexity between patients. SOURCE

That doesn't make the Finnish results meaningless.

It changes what can responsibly be claimed from them.

The study provides strong evidence that substantial psychiatric treatment needs persisted among these young people after medical gender reassignment.

It does not, by itself, prove the treatment created those psychiatric problems.

Researchers Are Debating the Interpretation

The paper has generated an unusually visible scientific discussion.

One published response argued that the study's outcome measures could produce misleading conclusions because psychiatric contact does not necessarily mean a patient's underlying condition worsened.

Another letter pointed to an earlier Finnish study involving 52 adolescents receiving hormones that reported reductions in treatment needs related specifically to depression, anxiety and suicidality or self-harm, despite specialist psychiatric treatment remaining common overall. SOURCE 

The authors of the new Finnish study have responded to criticism in Acta Paediatrica, and the journal has published multiple exchanges surrounding the paper. SOURCE 

This is what scientific disagreement often looks like.

Researchers can agree on the underlying data while disagreeing about how confidently those data answer a larger question.

What the Finnish Study Does Tell Us

Strip away the politics surrounding this subject and several findings deserve attention.

Young people referred for gender-related care in Finland had much higher levels of specialist psychiatric treatment than comparable young people in the general population, even before gender-clinic referral.

Those entering the system after 2010 arrived with considerably greater psychiatric treatment histories than earlier patients.

And substantial psychiatric treatment needs persisted after medical gender reassignment. SOURCE 

Those findings support the importance of comprehensive mental-health assessment and continuing psychiatric care rather than assuming gender-related medical treatment will, by itself, resolve every psychological difficulty a patient is experiencing.

They also raise a research question that this study cannot fully answer:

Why are psychiatric treatment needs remaining so high?

Possible explanations are not mutually exclusive. Preexisting psychiatric conditions may persist. New conditions may develop. Gender dysphoria itself may interact with other psychological difficulties. Social circumstances and stigma may affect mental health. Treatment could affect individuals differently. Increased engagement with healthcare could also increase the likelihood that psychiatric problems are identified and treated.

Separating those possibilities requires research designed specifically to distinguish them.

What It Doesn't Tell Us

The study does not demonstrate that every young person receiving gender-related medical treatment will experience worsening mental health, but it doesn’t tell us that it isn’t either.

It does not establish that the increase in psychiatric treatment was caused by hormones or surgery, but it may be that they do have a correlation.

It also does not establish the opposite, that medical treatment caused mental-health improvement.

The researchers themselves reported that psychiatric needs remained substantial after treatment. Other researchers argue that the study's design cannot determine how much of that outcome should be attributed to the treatment itself. SOURCE

hose are different questions.

And on a subject involving young people, medicine and irreversible decisions, that distinction matters.

The Finnish data provide something valuable precisely because they are extensive.

But large datasets still need careful interpretation.

The numbers deserve attention.

So do the limits of what those numbers can prove.