The UK’s High Court has rejected an application for a judicial review into a planned trial of puberty blockers for young people experiencing gender dysphoria.
Campaigners sought a judicial review of research planned by King’s College London, arguing that the study could harm participants. The application was rejected by Justice Chamberlain, who said none of the arguments presented appeared likely to succeed in court.
He said each patient involved in the planned Pathways trial would have been assessed by specialist doctors over many months before they had “formed the opinion that a child has a reasonable prospect of receiving a clinical benefit from the treatment”.
The university welcomed the decision and will now begin recruiting participants for the landmark study. Researchers will work with 220 children aged between 11 and 16 who are experiencing gender dysphoria.
A spokesperson for the university told The Guardian that the trial had been carefully designed.
“Pathways trial is a carefully designed study to give much needed evidence about the potential benefits and risks of puberty suppression to improve NHS care.
“A small number of young people with long-term gender incongruence, who have already received comprehensive psychological and social support through NHS gender services, will be eligible,” they said.
Opponents of the trial have argued that it does not meet appropriate ethical research standards, while the Opposition Spokesperson for Equality has called on the government to step in and stop the research.
Claire Coutinho MP, the Conservatives’ Shadow Minister for Equalities, said: “The puberty blocker trial will put hundreds of children, some as young as 11, on a pathway to infertility and serious medical consequences for the rest of their lives.
“No child can consent to this.
“This result is extremely disappointing, but it is now up to the government to do the right thing and stop the puberty blocker trial for good.”
The commencement of the trial was a recommendation arising from the 2024 Cass Review, a report that has attracted both support and criticism. The review, led by Dr Hillary Cass, described the field as an “area of remarkably weak evidence”. The findings have subsequently been challenged by some medical professionals, including a team in Australia that reviewed the report.
In Australia, Queensland and the Northern Territory have introduced restrictions on the use of puberty blockers and hormone treatments for young people experiencing gender dysphoria.
Queensland Health Minister Tim Nicholls has said results from the UK’s Pathways trial will be a factor in future consideration of the state’s policy settings. Nicholl’s ban on the use of medication in treating youth experiencing gender dysphoria is currently in place until 2030.
Australia’s federal Health Minister Mark Butler has also commissioned a national review. Interim advice on the use of puberty blockers was expected to be completed during 2026.
