NHS England is a slow learner. A year has passed since the closure of the Tavistock youth gender-identity clinic. It has been a decade since campaigners first questioned the surge in girls being prescribed puberty blockers there. And it is 20 years since psychotherapist Susan Evans blew the whistle on ‘gender affirming’ care. Yet here we are again. Just months after puberty blockers were permanently banned due to the lack of evidence supporting their safety, the NHS is now spaffing £10.7million on a new clinical trial for these drugs.
The so-called Pathways study, commissioned by the NHS and backed by the National Institute for Health and Care Research (NIHR), aims to ‘build the evidence base on the care needs and development of children and young people with gender incongruence’. This will include the use of gonadotropin-releasing hormone (GnRH) analogues – aka puberty blockers.
In principle, it sounds reasonable to gather more data before either cementing a ban or extending the use of an experimental drug. But the evidence base for the use of puberty blockers is ideological, not scientific.
The Cass Review, a comprehensive four-year investigation into NHS England’s gender-identity services, found that there was no evidence to support the use of the drugs in children. We do, however, know a great deal more about the damage they do, with side effects including damage to bone density, psychosexual development and cognitive function. The paediatrician who led the review, Baroness Cass, warned in a 2023 letter to an NHS boss that the drugs ‘may permanently disrupt the brain maturation of adolescents, potentially rewiring neural circuits that cannot be reversed’.
The new puberty-blocker study, which will be led by King’s College London and is set to run until 2031, is little more than an unnecessary experiment on some of the UK’s most vulnerable children. It has about as much medical merit as prescribing Ozempic to anorexics on the basis that the patients feel fat.
According to the details published by the NIHR, children will be handed puberty blockers if they ‘want to delay puberty’ and if their parents agree. After that, they’ll be monitored – for just two years – via ‘regular checks on their physical, social and emotional wellbeing’.
As Dr Louise Irvine of the Clinical Advisory Network on Sex and Gender explained to the Telegraph, the two-year monitoring period means that researchers are ‘putting children through the known risks of puberty blockers for no gain in knowledge’. The Cass Review, she points out, ‘said there was a lack of long-term outcome studies’, but this trial ‘is just more of the same’ of what’s already been done. ‘I consider it totally unethical’, she added. ‘[Researchers] are going to test for harms to cognitive development – but by the time they discover any harm it may be too late to do anything about it.’
One of the most persistent lies about puberty blockers is that they provide a neutral ‘pause’ – a harmless waiting period for a child to think through their gender identity. The evidence says otherwise. Almost every single child who takes them goes on to cross-sex hormones. Blockers don’t permanently stop gender distress, they lock it in, setting children on a medicalised path to sterilisation.
Marcus Evans, former Tavistock board member and psychotherapist, explained on X that, in his experience, offering puberty blockers was like ‘standing outside a drug rehabilitation service’ and giving addicts a choice between opium or psychological support: ‘Faced with that choice, the kids didn’t pause puberty and then return to a natural developmental pathway. They continued down the medical route. Ninety-five per cent moved from the allure of puberty blockers to the allure of cross-sex hormones.’
Evans also takes issue with the trial’s two-year monitoring period. ‘The consequences won’t be evident in two years, when individuals may still be caught in the euphoria of having seemingly triumphed over their biological development. The real reckoning will come in 20 years, after prolonged use of puberty blockers, cross-sex hormones and surgical interventions’, he warns. ‘That’s when we’ll see the full impact of this live experiment.’
What is perhaps most shocking is that had NHS clinicians done their jobs, the evidence would already be to hand. The Cass Review sought to uncover the fate of around 9,000 children seen at the Tavistock gender clinic – yet the service itself never bothered to follow up on any of its patients. Cass herself has noted that this research could have ‘helped develop a stronger evidence base about the types of support and interventions received and longer-term outcomes’, but it was ultimately ‘thwarted by a lack of cooperation from the adult gender services’.
The real issue isn’t whether these drugs are damaging. Ample evidence already shows they are. The real issue is the ongoing effort to justify and revive what has already been exposed as a catastrophic medical failure. Moreover, it is easy to forget the prescription of puberty blockers in the UK started out as a medical trial in the first place, albeit one for which evidence was never properly collected.
The NHS recognised that puberty blockers were harmful when it ended their routine prescription in March 2024. Yet instead of following the lead of Sweden, Finland, and Norway, which have pulled back on these treatments due to serious safety concerns, the UK is now ploughing ahead with bringing them back, eyes squeezed shut, fingers jammed in ears.
This is not science. This is not medicine. This is an exercise in ideological damage control, and the ones paying the price are the children.
Jo Bartosch is a journalist campaigning for the rights of women and girls.
