A U.K. court has ruled children are unable to consent to taking drugs to change gender, in a landmark case welcomed by Catholic doctors and a bishop.

Three judges at the High Court in London ruled Dec. 1 that drugs known as puberty blockers must not be given to children under 16 without permission from a court to confirm that such therapies were in the child's "best interests."

They said that a court judgment should also be sought if there was any doubt that patients up to the age of 17 years were not fully aware of the consequences.

The 19-page ruling makes doctors who act without such judgments legally liable for expensive clinical negligence claims from former patients.

Bishop Philip Egan of Portsmouth described the judgment as "a ray of common sense."

"As Christians, we believe that God creates people as male and female," he said in a Dec. 4 statement sent by email to Catholic News Service. "This is why gender dysphoria is a condition that needs to be addressed first and foremost by spiritual and psychological therapies, with real love and emotional support for the individual concerned, rather than leaping to surgical and hormonal interventions."

He said: "The primary aim of therapy should not be to help people physically change their sex, but to assure them that they are loving and loveable human beings and to help them find their true identity."

Dr. Dermot Kearney, president of the Catholic Medical Association, said in a Dec. 4 email to CNS that the ruling acknowledged "there are unknown potential dangers associated with such interventions that may cause lasting damage to children, both in childhood and in later years."

"People with gender dysphoria need understanding and help," he said. "There is no evidence, however, that interventions that reinforce or affirm a preferred gender rather than the gender genetically and biologically determined are helpful or indeed safe.

"The evidence suggests that preferred gender-affirming interventions do not reduce levels of depression, substance abuse, self-harm and suicide among those affected by this illness," Kearney said.

He said the current preferred approach "using pharmacological and highly invasive surgical strategies to deal with a complex psychiatric condition may represent bad medicine."

The ruling followed a case brought by Keira Bell against London-based Tavistock and Portman NHS Foundation Trust, which runs the U.K.'s most prominent sex-change service for children, and by the mother of a 15-year-old autistic girl who is on a waiting list for treatment.

Bell, 23, began taking puberty blockers at the age of 16 when she sought to become a man. She was injected with testosterone beginning at age 17 and underwent a mastectomy at 20 before she decided to "de-transition," only to find even the drug therapies had caused irreversible changes.

She argued that she had been unable to fully consent because of her age and alleged that there were insufficient safeguards to protect young people.

In their ruling, the judges said: "It is highly unlikely that a child aged 13 or under would be competent to give consent to the administration of puberty blockers.

"It is doubtful that a child aged 14 or 15 could understand and weigh the long-term risks and consequences of the administration of puberty blockers."

The trust has said it is "disappointed" by the judgment and would appeal to the U.K. Supreme Court to overturn it.

Gay rights groups in the U.K. have criticized the ruling, as well as Amnesty International and Liberty, a civil rights group.

"Young trans people should not have their access to health care restricted simply because they are trans," Amnesty and Liberty said in a joint statement posted online Dec. 3.

"There must be no further curbs to the bodily autonomy and determination of any young person, particularly young trans people and anyone who wants to access gender-specific health care," they said.

Paul Conrathe, Bell's lawyer, said in a Dec. 3 statement that his client would "vigorously defend" any appeal.