Hormone drugs will not be prescribed by the NHS to new under-18 patients who are transitioning genders following a review into the treatment's effectiveness.
The masculinising or feminising hormones have been available on the NHS for 16 and 17-year-olds diagnosed with gender dysphoria who meet certain criteria - but new referrals have been paused from Monday.
Any teenage patients in that age bracket currently receiving cross-sex hormones can continue to receive the therapy, but it must be reviewed individually with clinicians.
The NHS England review found the evidence is too weak to show whether such medication is beneficial or harmful to children with gender dysphoria.
It is understood the NHS is continuing to look at evidence for masculinising and feminising hormones for adults.
A 90-day consultation on plans to remove the treatment as a routine procedure on the NHS has now begun.
The treatment will be paused throughout this period and while NHS England reviews the expected thousands of responses before making its final decision.
The hormones can cause irreversible changes, such as deepening of the voice when taking testosterone, or breast development when taking oestrogen.
Long-term gender hormone therapy can cause temporary or even permanent infertility, the NHS says.
Read more from Sky News:
Vape shop fire closes railway station
Oil's biggest one-day rise in six years
In the 2024 Cass Review into children's gender care, Baroness Hilary Cass recommended "extreme caution" in providing such drugs, as well as a "clear clinical rationale for providing hormones at this stage rather than waiting until an individual reaches 18".
A clinical trial into the impacts of puberty blockers on children as young as 10, launched in November, was paused last month.
This was before anyone had been recruited - amid concerns over the "unquantified risk" of "long-term biological harms".
Use of the drugs to delay or prevent puberty was banned for under-18s in 2024.
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 - in accordance with the advice from Dr Cass - and as part of this action will now be pausing any new referrals for this treatment for 16 and 17-year-olds.
"The NHS continues to offer specialist support for under-18s managing gender incongruence, including mental health support and referral to specialist children and young people's gender services where appropriate."
(c) Sky News 2026: Gender-affirming hormone treatment for teenagers halted by NHS
Fire shuts Scotland's busiest train station for at least two days
Police appeal for help to identify man found dead in a wetsuit
Cancer death rates fall to historic low - as types with biggest drop in fatalities revealed
Gerry Adams 'directly responsible' for bomb decisions, High Court told
Diane Sindall: Family of murder victim appeal for information after wrongful conviction
Spend more on defence or risk being vulnerable to missile and drone attacks, UK warned
Rangers and Celtic fans in 'shameful' clashes on pitch after Scottish Cup tie
Lib Dem leader calls for King's US state visit to be cancelled after Trump's criticism of Starmer
The 'dropping tax band' trick that could boost your pension | Money newsletter
