Trialling puberty blockers for under-18s puts young people at risk – it should not go ahead
Dr Hilary Cass and the Independent Review of Gender Identity Services for Children and Young People, The Cass Review, April 2024 (PA Images / Alamy Stock Photo)
4 min read
The UK has witnessed a sharp and troubling rise in the number of children and adolescents presenting with gender-related distress in recent years.
Between 2009 and 2016, referrals to the NHS Gender Identity Development Service (GIDS) surged from 51 to 1,766. This is a shocking increase, but perhaps more striking is that the demographic flipped from predominantly boys to a majority of girls – many of whom also struggle with mental health issues, autism, trauma, or have a history of being in care. This is not just a cohort grappling with identity. It is one of the most vulnerable populations in our society.
What has driven this dramatic increase remains uncertain. Theories range from the 24/7 influence of online culture to greater social acceptance of trans identities and shifts in how young people process identity and sexuality. Social factors such as the media, peer groups and institutional visibility certainly play a role. But amid all the speculation, one thing is clear: we need caution, not haste.
The Pathways trial risks enshrining a treatment pathway that lacks proven benefit and carries very real harms
Historically, the NHS approach was one of “watchful waiting” – a therapeutic stance, grounded in evidence that most children with gender distress outgrow it after puberty. Early studies showed that between 67 and 90 per cent of such children come to reconcile with their birth sex. But the clinical landscape shifted with the adoption of the “Dutch Protocol” in the 2010s, introducing puberty blockers as a treatment option. Originally used to delay precocious puberty, these drugs are unlicensed for gender dysphoria.
The rationale was to “pause” puberty and give children space to explore their identity. But real-world outcomes have diverged dramatically from this benign ideal. Not only do most children who begin puberty blockers go on to take cross-sex hormones, but studies – including the NHS’s own research – have failed to show improvements in gender dysphoria or mental health. In some cases, outcomes worsened, particularly among girls, with increases in self-harm and suicidal ideation.
The Cass Review – an independent, evidence-led assessment – offered a sobering conclusion: the evidence base for puberty blockers is “remarkably weak”. Bone density, height, brain development and future sexual function may all be negatively affected. Adolescence is a critical window for neurodevelopment, and halting this natural process may do irreversible harm. Given these findings, the government acted responsibly in 2024 by banning the use of puberty blockers for gender dysphoria in minors.
Now, the Department of Health has announced the £10.7m Pathways trial, set to begin in 2025 and run through 2031. This trial aims to study the effects of puberty blockers on the “physical, social and emotional wellbeing” of participants over two years. But this raises profound ethical questions.
Why, given the extensive data from over 9,000 GIDS patients already treated, do we need another trial at all? Why only track outcomes for two years, when the most serious consequences, such as infertility or impaired sexual function, may not emerge until adulthood? Why are same-sex attracted and neurodiverse youth over-represented in the cohort being medicalised, and are their unique vulnerabilities being adequately safeguarded?
Informed consent is another flashpoint. Can a 13-year-old child possibly comprehend the lifelong implications of losing fertility, or the psychological toll of irreversible medical transition? These are healthy children, not terminally ill patients for whom the risk-benefit calculus might justify experimental treatments. The principle of “do no harm” must weigh heavily here.
Gender incongruence is an extremely distressing condition, but the medical response must be beneficial and, most importantly, safe. The Pathways trial risks enshrining a treatment pathway that lacks proven benefit and carries very real harms.
We owe it to this generation to demand better. Instead of medicalising adolescents, we should be asking why so many young people are in distress in the first place. We should offer robust, evidence-based psychological support, and allow time and space for identity to develop without irreversible interventions.
A permanent ban on puberty blockers was the right step. Launching a new trial, when there is already existing data on the harms, is not. The children in this debate are not ideological pawns; they are young people with their whole lives ahead of them. We must not gamble with their health.
Rebecca Paul is Conservative MP for Reigate
