A new Finnish nationwide register study finds that young people sent to specialised gender clinics already had far more severe psychiatric illness than matched peers — and that those needs did not fade after what the authors call “medical gender reassignment” (sex-rejecting hormones or surgery). This is an observational records study, not a gold-standard random-assignment trial.
Ruuska S-M, Tuisku K, Holttinen T, and Kaltiala R published “Psychiatric Morbidity Among Adolescents and Young Adults Who Contacted Specialised Gender Identity Services in Finland in 1996–2019: A Register Study” in Acta Paediatrica (online 4 April 2026; print July 2026). They followed every person under 23 referred in those years — 2,083 people — against 16,643 matched controls.
Severe psychiatric morbidity was about 45.7% in the referred group before referral versus about 15.0% in controls, and about 61.7% versus about 14.6% two or more years after referral. People referred after 2010 had greater psychiatric need than earlier cohorts. Among those who underwent medical gender reassignment, psychiatric morbidity rose over follow-up — about 9.8% to 60.7% in feminising treatment, and about 21.6% to 54.5% in masculinising treatment (the paper’s figures). After prior psychiatric treatment was accounted for, the authors report hazard ratios about three times female controls and about five times male controls.
The authors conclude that psychiatric needs do not subside after medical gender reassignment.
A Finnish records study is also on Facts, under Industry documents — not one of the six systematic reviews: [Finland register study — Ruuska et al. 2026](/facts/documents#ruuska-finland-psychiatric-morbidity-2026). The 2024 Ruuska suicide-death paper is on Suicide Myth.
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