The focus on puberty blockers in the gender-care debate is disproportionate, the paediatrician who led the NHS review into children’s services, says.

Dr Hilary Cass said the merits of the treatment used to delay the onset of puberty had been “oversold” and there was “very limited” evidence they were of use.

Adults with long-standing trans identity should be offered medical interventions, she told BBC News, but it was right to be careful with children questioning their gender, who were in a “dynamic state of development”.

It follows a ban, earlier this year, on the routine prescription of puberty blockers for children with gender dysphoria.

The ban, in response to Dr Cass’s landmark review, led to criticism from the British Medical Association (BMA) and campaigners taking legal action against it.

The BMA, which has since rowed back on its criticisms after a backlash by doctors, had called Dr Cass’s recommendations “unsubstantiated”.

And one of its senior leaders had claimed banning puberty blockers could cause “incredible harm“ to trans people.

The review, commissioned by NHS England and published in April, called for better psychological support, noting young people struggling with their gender had higher rates of mental-health problems and neurodiversity such as autism and ADHD or childhood trauma.

On Wednesday, Dr Cass told BBC Radio 4’s Woman’s Hour programme: “They [puberty blockers] have been a disproportionate amount of the discussion, because actually the evidence doesn’t show benefit for the majority of young people who go on them.

“And in some senses, they have been oversold to young people as being the thing that is going to make them feel dramatically better.”

Puberty blockers were prescribed to children by London’s Tavistock Clinic, which was the only NHS gender service for under-18s but has now been closed down.

There was “very limited” evidence they could help, Dr Cass told Woman’s Hour.

They could be used for a small number of young people “but we just don’t know who they are”.

“We don’t know if the harms outweigh the benefits in other young people,” Dr Cass told the programme.

“If I was pitching any other drug to give to children with that kind of data, you would say, ‘no way.’”

Better evidence was needed, so the NHS was setting up a clinical trial into their use.

And medical and surgical interventions for children transitioning gender required extra care, because they were in a “dynamic state of development”.

“We just don’t know which way they are going to go in adulthood,” Dr Cass told Woman’s Hour.

“If they go down the wrong pathway for them, then the costs in terms of medical intervention are gravely heavy to bear, when some of the effects are irreversible.”

But for adults with an “enduring and long-standing trans identity”, the costs of medical intervention were “trivial” compared with “how difficult it would be not to be able to live in your identified gender”.

“For those people, it is absolutely crucial they get the clinical intervention they need and want,” Dr Cass told the programme.

She also said the BMA’s objections did not “matter”, as NHS England was already pushing ahead with a new network of services emphasising the provision of more holistic care to children and young people.

Earlier this year, the doctors’ union called for a pause to the implementation of the Cass Review and the ban on puberty blockers to be lifted.

But it later said it was moving to a neutral position after the backlash by doctors.

The BMA is carrying out its own review into gender services for children.

Dr Cass said she found the union’s position “puzzling” and urged it not to “cherry-pick” the evidence.