The Court of Appeal in London on Friday ruled that doctors can give puberty blockers to children under 16 who wish to undergo gender reassignment, provided they believe adolescents are in a position to consent.

The ruling overturns a decision in the High Court last year that said it was "highly unlikely" a child under 13 "would be competent to give consent to the administration of puberty blockers".

It also said it was "very doubtful" a child of 14 or 15 would understand the long-term consequences.

The case was brought against Britain's only gender identity development service for children, run by the Tavistock and Portman NHS Trust, which has long faced criticism it is too quick to prescribe the treatment.

Lawyers for a woman who took hormone blockers aged 16, before de-transitioning, and the mother of a 15-year-old girl, argued children could not properly understand the nature and effects of the drugs.

But the Court of Appeal on Friday said it was up to doctors to decide whether patients could properly consent.

"The court was not in a position to generalise about the capability of persons of different ages to understand what is necessary for them to be competent to consent to the administration of puberty blockers," the three appeal judges said in their ruling.

"It placed patients, parents and clinicians in a very difficult position," they added.

'For doctors, not judges'

The Tavistock and Portman NHS Trust has seen a huge rise in recent years of referrals of children from across Britain, from 1,408 in 2015-16, to 2,728 in 2019-20.

It argued the initial ruling was "inconsistent" with the established standard that could consent to their own , and welcomed the appeal ruling.

"The judgment upholds established legal principles which respect the ability of our clinicians to engage actively and thoughtfully with our patients in decisions about their care and futures," it said in a statement.

"It affirms that it is for doctors, not judges, to decide on the capacity of under-16s to consent to medical treatment."

Proponents argue that artificially pausing puberty gives a young person time to consider their options, without the stress of unwanted changes to their body.

But clinicians say there may be longer-term effects on fertility, sexual function and bone density, although evidence is limited.

Keira Bell, 23, who brought the case, said she was "obviously disappointed" with the ruling, "especially that it did not grapple with the significant risk of harm that children are exposed to by being given powerful experimental drugs.

"I am surprised and disappointed that the court was not concerned that children as young as 10 have been put on a pathway to sterilisation," she said.

"It has shone a light into the dark corners of a medical scandal that is harming and harmed me."

Nancy Kelley, chief executive of LGBT charity Stonewall, said that the outcome "will be a huge relief for trans young people and their families, as well as the wider trans community."