Debate › AUMC response · Last reviewed 2026-05-16
Response VUmc / Amsterdam UMC
Summary
Researchers at Amsterdam UMC — including Annelou de Vries, Thomas Steensma, Maartje van der Loos and Daniel Klink — have responded to international criticism in various peer-reviewed publications. Their consistent position is that the outcomes of the original protocol have been confirmed in later Dutch cohort studies, that international implementation has diverged from the Dutch model and that the Cass Review's interpretation of the evidence is contested. See also /protocol/current-status-netherlands/.
1. Main publications of the AUMC team (since 2020)
- van der Loos MATC, et al. Continuation of gender-affirming hormones in adolescents and young adults. Lancet Child Adolesc Health. 2022;6(12):869–75. → follow-up overview
- van der Loos MATC, et al. Bone mineral density in transgender adolescents treated with puberty suppression. JAMA Pediatr. 2023.
- Brik T, et al. Trajectories of adolescents treated with gonadotropin-releasing hormone analogues. Arch Sex Behav. 2020;49(7):2611–8.
- de Vries ALC, Richards C, Tishelman AC, et al. Bell v. Tavistock and the future of gender-affirming care for trans and gender diverse youth. Int J Transgender Health. 2021;22(3):217–24. → /debate/legal-cases/
2. Core points of the Dutch response
- Continuation rates: 96–98% of adolescents who receive GnRHa progress to CSH — interpreted as confirmation of diagnostic certainty. See /protocol/the-three-phases/.
- Bone density: van der Loos (2023) reports recovery of bone mineralisation after the CSH phase.
- Discontinuation/regret: 1.9% stop before CSH; 0.5% report regret after CSH (cohort of 1,766) — see /debate/detransition-research/.
- International implementation: the Dutch team points out that deviations from the protocol elsewhere (shorter diagnostics, looser criteria) cannot be attributed to the Dutch Protocol itself — see /international/spread/.
3. Response to the Cass Review
Annelou de Vries and colleagues published a commentary in BMJ in May 2024 stating that the Cass Review report "under-illuminated the broader context and clinical reasoning behind gender-affirming care for adolescents". WPATH Europe published a more extensive rebuttal in July 2024.1
See also
- People register — de Vries, Steensma, van der Loos, Klink.
- International comparison.
- Timeline.
- Current status Netherlands — the clinical practice on which AUMC bases its position.
- Changes over time — how the Dutch protocol has evolved.
- Follow-up studies — overview — research publications by the AUMC team.
- Cass Review (2024) — the focus of the Dutch response.
- Scientific criticism — criticism to which AUMC responds.
- International spread — deviations from the Dutch model elsewhere.
- Guidelines Netherlands — official Dutch guidelines.
- FAQ · Glossary · For journalists.
Footnotes
- de Vries ALC, et al. Gender-affirming care for trans youth: response to the Cass Review. BMJ. 2024.