The landscape of gender care for young people in the UK is set for a significant shift as researchers announce two major clinical studies into the effects of puberty blockers. This move comes directly in response to the landmark 2024 Cass review, which concluded that evidence supporting the use of these drugs for children experiencing gender incongruence was built on 'shaky foundations'.
The Cass Review and a New Direction for Care
Last year, NHS England made a pivotal decision: children with gender dysphoria would no longer receive puberty blockers as a routine practice. This policy change restricted their use solely to research settings. The independent Cass review had identified a critical gap, finding 'insufficient/inconsistent evidence' about the effects of puberty suppression on crucial areas like psychological wellbeing, cognitive development, and fertility.
Puberty blockers, originally developed to treat early onset puberty, have been used off-label for young people with gender dysphoria. The new 'Pathways' research programme aims to finally build a robust evidence base for their application in gender services.
Inside the Pathways Clinical Trials
The research consists of two distinct studies. The first, the Pathways Trial, is a clinical study planning to recruit approximately 226 young people over the next three years. Participants, who will be aged between roughly 10-11 and 15 years 11 months, will be randomised into two groups.
One group will begin taking puberty blockers immediately, while the other will start after a 12-month delay. All participants will receive a wider package of care and support, and their health and development will be meticulously monitored for a period of 24 months. At the trial's conclusion, each young person will be individually reviewed to determine their ongoing care needs, which could include continuing on the medication.
The second study, Pathways Connect, will involve about 150 participants from the main trial and an additional 100 young people not receiving puberty blockers. This part of the research will use MRI brain imaging, with results analysed alongside cognitive task performance. The research team has stated it will be at least four years before any findings are published.
Ethical Concerns and Research Imperative
The design of the trial has drawn criticism from some advocacy groups. Chay Brown, health director for TransActual, described the study as 'coercive in nature'. He expressed deep concern that it is the only route to accessing puberty blockers through the NHS and argued that the randomised delay means some young people will experience distressing pubertal changes that others will not.
However, Professor Emily Simonoff, the chief investigator from King's College London, offered a different perspective. She suggested that puberty blockers should perhaps never have been made available outside of a clinical trial a decade ago. 'The most ethical thing would have been to do a trial at that point in time,' she stated, framing the current studies as a necessary step to establish safe and effective care protocols based on solid evidence.
