The trade union representing doctors across the UK has dropped its opposition to the findings of the Cass review of gender identity services across the NHS.

The British Medical Association (BMA) had previously rejected the findings of the landmark review of transgender healthcare, with the medical body refusing to endorse the report’s findings.

The review, published in April 2024 and conducted by Dr Hilary Cass, found children and young people had been let down by a lack of research and evidence on medical interventions, and NHS gender medicine was “built on shaky foundations”.

The BMA’s council voted to oppose the implementation of the review, saying its findings were “unsubstantiated”.

On Wednesday, the body published a long-awaited review of Cass’s findings, conducted by 12 union members.

Prof David Strain, the chair of the BMA’s board of science, who led the review, said the Cass report’s methodology was robust and the BMA was no longer opposed to any of its 32 recommendations.

“A strength of this work has been the ability of clinicians with differing perspectives to engage constructively to ensure the concerns of the profession and those with lived experience were explored,” said Strain.

“While interpretations and policy preferences in the group, as in the profession indeed in wider society, have diverged, there has been consistent respect for the underlying data and for the ethical complexity of the decisions involved.”

He added: “This report identifies the need to make significant improvements in the way in which gender identity services for children and young people are provided. As in many other treatment areas, it also highlights the ongoing challenge of managing uncertainty for the medical profession when caring for people with gender incongruence in a way that is proportionate, transparent, and patient-centred.”

Despite the BMA’s report largely vindicating the findings of the Cass review, the trade union body also claimed some of the government’s actions in the aftermath of the review, such as banning puberty blockers on the NHS, went beyond Cass’s recommendations.

The union said it was “continuing to oppose a ban on puberty blockers for several reasons, not least because it is a threat to the autonomy of a doctor. We spend decades training on how to use drugs, and to have a political decision affecting the way we prescribe is wrong.”

A key finding of the Cass review, which took four years and was based on data from 113,000 children, was that there was no evidence to support prescribing sex hormones to under-18s.

Her report also found young people often present with complex needs, including trauma, self-harm, depression, and these factors were sometimes not adequately explored before medical treatment pathways were considered.

As a result of the Cass review, the Tavistock clinic in London, which was the UK’s only NHS gender identity development service, was permanently closed in March 2024. The service treated about 9,000 children and young people, with an average referral age of 14, between 2009 and 2020.

NHS England has been approached for comment.