December 3, 2020

UK High Court Ruling on the Use of Puberty Blockers in Gender Dysphoric Minors (Bell v. Tavistock)

SEGM position statement

The Society for Evidence-Based Gender Medicine (SEGM) maintains that treatments for gender-dysphoric people should be supported by high quality evidence. We commend the thorough process undertaken by the UK High Court to assess the ability of young people to consent to treatment that has serious side effects and lacks adequate supporting evidence.

The UK High Court determined that the provision of puberty blocking medications (GnRHa) to stop normally-timed puberty in gender dysphoric young people is experimental (1). The judges recognized puberty blockers as the first step in a trajectory that almost invariably leads to later prescription of cross-sex hormones with irreversible consequences. Because of this, the Court ruled that persons under age 16 are unlikely to be able to provide valid informed consent, as they lack the capacity to properly comprehend and evaluate the profound and life-long impacts of these interventions. Additionally, the Court issued caution for those between the ages of 16-17, as young people have a limited ability to comprehend the profound life-long implications for sexual and reproductive function and other health risks. With this ruling, the High Court has set up an expectation of accountability of the health professionals engaged in the provision of pediatric medical transition.

The UK High Court’s conclusions reflect growing concern among a significant number of researchers and clinicians about the poorly understood rapid rise in the number of adolescents with gender dysphoria, and the marked lack of evidence that hormones and surgery improve long-term health outcomes.

Three separate reviews of the scientific literature (a review by Professor Carl Heneghan, the director of the University of Oxford's Centre for Evidence-Based Medicine; the Swedish Health Authority evidence review; and the Finnish Health Authority evidence review) conclude that the research evidence for hormones to alleviate gender dysphoria in young people is insufficient,(2–4) rendering these interventions experimental. The Endocrine Society, which outlined this hormone protocol for young people, also conducted a review of the evidence and concluded that the quality of the evidence was low to very low (5). [Update: In 2020, the UK National Institute for Health and Care Excellence (NICE) undertook two systematic evidence reviews of hormonal interventions for gender-dysphoric youth and concluded that the evidence basis is of very low quality, calling for a need to carefully weigh the low-certainty benefits against the significant risks of these interventions.] 

Gender medicine is a relatively new field with a limited and shifting evidence base. In 2020, the scientific debate about biomedical interventions for gender dysphoria intensified as serious methodological flaws and misinterpretations of studies underpinning the current treatment model were exposed. A major study alleging evidence of mental health benefits of biomedical treatment for adults was corrected; a revision concluded that neither hormones nor surgery are of any benefit in terms of long- term mental health or suicidality (6). Two other widely cited studies purporting benefits of puberty blockers and suggesting harms of psychological approaches to gender dysphoria were also found to have errors and misrepresentations that invalidated the papers’ conclusions (7,8).

The author of the experimental protocol of biomedical interventions for young people (known as the Dutch protocol) published a commentary in Pediatrics in October 2020 alerting the medical community that biomedical transition is currently being applied to young people for whom it was not designed and might not benefit (9). The author emphasized the need to identify those people who need enhanced mental health support, rather than gender reassignment.

There has been a marked and poorly understood change in the profile of the young gender-dysphoric patients in recent years, from primarily males with childhood-onset gender dysphoria, to predominantly females with adolescent-emergent gender distress and a significant burden of comorbid trauma, mental illness, and neurodevelopmental difficulties. This recent phenomenon has been noted by gender clinics worldwide, highlighting how little is currently known about which approaches will lead to optimal outcomes in this population.

Based on the current research and documented evidence, SEGM asserts that the long-term outcomes of puberty blockers for the treatment of gender dysphoria are not known. Numerous outcomes are yet to be clarified, including whether there is long-term psychological harm or benefit, whether suicide rates are increased, decreased or unchanged, and whether blockers contribute to longer-term persistence of gender dysphoria, necessitating life-long medical treatment with adverse impacts on morbidity and mortality.

Describing puberty blockers as simply a “pause button,” “completely reversible,” “life-saving,” or “evidence-based” is untrue and misleads patients, their families and the clinicians responsible for their long-term health. The prescription of puberty blockers to gender-dysphoric young people with normally-timed puberty is experimental. Thus, puberty blockers should only be offered in formal, approved research settings, with rigorous study designs capable of generating useful information.

Overconfidence is dangerous in science and medicine. All ethical practitioners must humbly recognize the significant uncertainties in the field of gender medicine. We sincerely hope that the judgement of the High Court will mark the beginning of international commitment to rigorous clinical investigation into the most effective treatments for children and adolescents experiencing gender dysphoria. Until a reliable, quality evidence base emerges, young patients and their families should be supported in exploring all available options before undergoing invasive, often irreversible interventions with unknown long-term implications.

Roberto D’Angelo, PsyD, MMed, MBBS, FRANZCP
SEGM President

William Malone, MD, SEGM Director
Julia Mason, MD, SEGM Director
Stephen Beck, MD, FACP, SEGM Director
Marcus Evans, SEGM Director


  1. Bell-v-Tavistock Judgement. Published online December 1, 2020. Accessed December 2, 2020.
  2. Heneghan, Carl, Jefferson, Tom. Gender-affirming hormone in children and adolescents. BMJ EBM Spotlight. Published February 25, 2019. Accessed October 9, 2020.
  3. SBU [Swedish Health Authority]. Könsdysfori hos barn och unga: En kunskapskartläggning [Gender Dysphoria in Children and Adolescents: An Inventory of the Literature. Systematic Scoping Review.] Swedish Agency for Health and Technology Assessment and Assessment of Social Services. 2019. Accessed December 1, 2020.
  4. Palko [Finnish Health Authority / Council for Choices in Health Care in Finland]. Palveluvalikoimaneuvoston suositus: Alaikäisten sukupuoli-identiteetin variaatioihin liittyvän dysforian lääketieteelliset hoitomenetelmät [Gender Dysphoria in Children and Adolescents: Recommendation for Treatment Approaches]. 2020. Accessed December 1, 2020.
  5. Hembree WC, Cohen-Kettenis PT, Gooren L, et al. Endocrine Treatment Of Gender-Dysphoric/Gender-Incongruent Persons: An Endocrine Society Clinical Practice Guideline. Endocrine Practice. 2017;23(12):1437-1437.
  6. Correction to Bränström and Pachankis. AJP. 2020;177(8):734-734.
  7. Biggs M. Puberty Blockers and Suicidality in Adolescents Suffering from Gender Dysphoria. Arch Sex Behav. 2020;49(7):2227-2229.
  8. D’Angelo R, Syrulnik E, Ayad S, Marchiano L, Kenny DT, Clarke P. One Size Does Not Fit All: In Support of Psychotherapy for Gender Dysphoria. Arch Sex Behav. Published online October 21, 2020.
  9. de Vries ALC. Challenges in Timing Puberty Suppression for Gender-Nonconforming Adolescents. Pediatrics. 2020;146(4):e2020010611.