NHS England has paused new prescriptions of cross-sex hormones to 16 and 17-year-olds who question their gender, after a review found previous research into how harmful or beneficial the drugs may be was « really weak ».
Hormones can be prescribed to help a person develop characteristics associated with their preferred gender rather than their biological sex, and may produce irreversible changes like a deeper voice or breast growth.
The health service said a small number of teenagers would be affected and launched a consultation on longer-term guidance over use of the treatment.
One trans advocacy group has said it would consider legal action over the move.
Young people who are already being prescribed the hormones will continue to get them but their clinicians will be asked to review their treatment.
Existing guidance says the hormones should not be prescribed to under-16s for gender treatment.
NHS England said young people who can not access the treatment will be offered other forms of care at three NHS gender clinics for children currently operating in England.
The review was triggered following the publication of a major report into children’s gender care by Dr Hilary Cass in April 2024, which said « remarkably weak evidence » on medical interventions was letting children down.
NHS England said it commissioned 10 independent evidence reviews to examine different aspects of the use of testosterone or oestrogen, either on their own or with other drugs for young people who identify as a gender different to their biological sex.
It found there was not enough good quality evidence to conclude overall whether the drugs benefited young people or harmed them, so NHS England will not issue new prescriptions while it continues to consider responses from advocacy groups and healthcare professionals.
It looked at what impact the hormones had on a range of outcomes for young patients distressed about their gender, including quality of life and mental health.
Professor James Palmer, National Medical Director for Specialised Services at NHS England, said: « The NHS has exercised extreme caution when considering starting young people on this treatment. »
He said the review had been « exceptionally thorough and complex » and had « established that the available evidence does not support the continued use of masculinising or feminising hormones to treat » young people under 18 with gender dysphoria or gender incongruence.
That meant « we cannot say if they are harmful or effective », he added.
A 90-day public consultation on the revised policy and review findings will start on Monday.
NHS England said it hoped the consultation will help it check whether any evidence has been missed, and that it will make a decision about longer-term guidance as soon as it can.
Trans advocacy group TransLucent said the move was « yet another blatant act of discrimination against transgender youths’ healthcare, which has been systematically eroded since the Cass Review ».
A statement continued: « We will critically assess the NHS’s evidence before responding, but given the gravity of these human rights concerns, we will consider legal action. »
The changed guidance on the use of cross-sex hormones applies only to the NHS, not to doctors working privately.
There is only one privately run gender clinic that is registered with the UK regulator, the Care Quality Commission. The Gender Plus hormone clinic is rated outstanding.
Paul Carruthers, nurse consultant and manager of the clinic, said they were dismayed by the decision, adding that they use a rigorous process in line with international standards before hormones can be prescribed.
He said: « NHS England’s interpretation of the evidence is in contrast to every reputable expert body in the field of transgender healthcare and, as such we will assess their policy document and evidence-based review to better understand how they arrived at this decision. »
The Department of Health and Social Care said: « The safety and wellbeing of children and young people is paramount and NHS England follow expert scientific and clinical advice when making decisions relating to clinical policies. »
Helen Joyce, director of advocacy at sex-based rights charity Sex Matters called the prescription of cross-sex hormones to under-18s « outrageous » and said the « pause to take stock of the evidence is long overdue ».
« Under-18s are simply too young to consent to such irreversible, life-changing consequences, » she said.
Last year a legal case was brought by campaigners against the government over the prescription of cross-sex hormones to 16 and 17-year-olds.
It was led by Keira Bell, who was prescribed testosterone as a teenager. At the time, she identified as a male, but says she now regrets taking medication that altered her body permanently.
Her case was dismissed in May 2025, but at the time, the health and social care secretary, Wes Streeting MP, said he was « actively considering » banning or restricting their use for young people, but was waiting for a review to be completed.
