The High Court previously ruled that children under 16 with gender dysphoria can only consent to the use of hormone-blocking treatments if they can understand the “immediate and long-term consequences”.
However, the judges said it was “highly unlikely” that a child aged 13 or under would be able to consent to the treatment, and that it was “doubtful” that a child of 14 or 15 would understand the consequences.
The original case was brought by Keira Bell – a 24-year-old woman who began taking puberty blockers when she was 16 before later “detransitioning” – against the Tavistock and Portman NHS Foundation Trust, which runs the UK’s only gender identity development service for children.
A mother of an autistic teenager who is on the waiting list for treatment, only known as Mrs A, supported Ms Bell in their successful legal challenge.
The Tavistock and Portman NHS Foundation Trust challenged the ruling, which was heard over two days at the Court of Appeal.
The court heard the Tavistock does not provide puberty blockers itself but instead makes referrals to two other NHS trusts – University College London Hospitals and Leeds Teaching Hospitals – who then prescribe the treatments.
Fenella Morris QC, for the Tavistock, said the decision “reset almost half a century of established law” and caused “serious distress to many young people and their families”.
Ms Morris told the court that reversible puberty blockers are used “to reduce distress” for children with gender dysphoria, allowing them to make decisions about their bodies in the future.
She continued: “Having reduced that distress, it creates the possibility to take time to consider options… it allows the child to make the choice.”
Human rights group Liberty, which intervened in the appeal, argued that the ruling imposed a serious restriction on the rights of transgender children and young people to “essential treatment”.
“Treatment for trans children and young people is particularly important and time-sensitive because failure to provide it leads them to irreversibly develop further characteristics of their birth sex, which can cause serious harm to their mental health and make subsequent treatment more invasive,” their barrister Jason Coppel QC said.
Jeremy Hyam QC, representing Ms Bell and Mrs A, told the court that the appeal should fail as it did not find any “material errors” in the original ruling.
He said that policies and procedures at the Tavistock “as a whole failed to ensure, or were insufficient to ensure, proper consent was being given by children who commenced on puberty blockers”.
The barrister also told the court there was an “inevitable or inextricable progression” from puberty blockers onto cross-sex hormones and that the judges were right to say a child would need to understand the impact of cross-sex hormones before being allowed the puberty-blocking treatment.
Mr Hyam added: “Right at the heart of what the court was concerned about was how can it be said that children of 10, 11, 12 have any proper conception of what sexual function is.”
Ms Morris had previously told the court it was not inevitable for a young person to move onto cross-sex hormones after 16 though a majority did do so.
John McKendrick QC, for the other trusts, told the court the median age for consenting to puberty blockers is 14.6 for UCL and 15.9 for Leeds.
At the end of the hearing on Thursday, the Lord Chief Justice Lord Burnett said the court’s ruling will take “a little while”.
Lord Burnett, sitting with Sir Geoffrey Vos and Lady Justice King, said: “We will of course take time to consider our decision.
“We are not in a position to say how long it will take us to produce our judgments, you have given us a lot to think about.”