Finland register study — Ruuska et al. 2026

Finland followed every person under 23 who contacted a specialist gender clinic from 1996 to 2019 — 2,083 people — and compared them with 16,643 matched peers in official records, for up to 25 years. Serious psychiatric illness was already much more common before referral. It did not fade after hormones or surgery.

• Before referral, about 46% already had serious psychiatric illness, versus about 15% of matched peers. From two years after referral onward it was about 62% versus about 15%.
• People referred after 2010 had even greater psychiatric need than earlier cohorts.
• Among those who received cross-sex hormones or surgery, psychiatric illness rose from before the first clinic visit to any time from two years after it — about 10% to 61% in males, and about 22% to 55% in females (about 19% to 56% combined).
• After prior psychiatric treatment was counted, referred youth still had about three times the psychiatric-illness risk of female peers and about five times that of male peers.
• In a later analysis (September 2026), counted from each person’s last completed step — cross-sex hormones, chest surgery, or genital surgery — about 19% had needed specialist psychiatric care before their first clinic visit and about 49% after the last procedure. Matched peers went from about 14% to about 13%. This count starts after the last procedure rather than two years after the first visit, so it covers a shorter period.
• Nearly 50 researchers and clinicians signed a letter of concern to the journal. The authors published two replies with further analyses and stood by their findings.
• The authors: psychiatric needs do not subside after medical transition.

Educational templates on minors’ medical limits are in the model legislation library, for learning and reference.