Puberty blockers: Ministry of Health releases long-awaited evidence brief

Evidence on the benefits and risks (or lack of either) - of puberty blockers when used to treat gender dysphoria in children and young people is limited, the Ministry of Health says.

In releasing its long-delayed evidence brief on Thursday, the ministry urged "a more precautionary approach" for the care of adolescents with gender identity issues.

"The ministry's assessment is that the starting point for treatment is a holistic assessment determining the full spectrum of needs a young person may have, including social and mental health," it said in a statement.

"The new precautionary approach signals the need for clinicians to exercise caution in prescribing, including that prescribing should only be initiated by clinicians who are experienced in providing gender-affirming care, and are part of an interprofessional team offering a full range of supports to young people presenting with gender identity issues."

The evidence brief of the use of the GnRHa hormones found:

• Evidence about the impact on clinical and mental health and wellbeing outcomes was scarce, with available evidence largely of poor quality
• Most studies were based on small numbers and short-term outcomes
• Bone health and metabolic parameters needed ongoing monitoring.

The evidence brief surveyed more than 4000 papers from international and national literature published up until 30 September 2023, of which 20 examining clinical outcomes and 10 investigating mental health outcomes met the criteria for inclusion.

An addendum to the evidence brief reviewed an additional 160 articles published between October 2023 and May 2024, which including the Cass Report, commissioned by the British government.

The move followed developments overseas to restrict the use of puberty blockers after rapid rises in recent years of the number of young people being treated for gender identity issues.

In New Zealand, around 25 young people aged 11 and 17 years were typically started on treatment with these medicines in 2010, and by 2021 the number had grown to around 140, before dropping last year to 113.

Use of puberty blockers in the UK is now limited to clinical trials, with similar restrictions already in place in Sweden, Finland and France.

The government has now tasked the ministry with consulting on whether the new precautions should be backed by "additional safeguards".

"These tighter controls reflect a level of concern both here and overseas about the increasing use of these medicines for the treatment of gender identity issues without sufficient evidence to support their safety and effectiveness both now and in the longer-term," a spokesperson said.

"The appropriate and safe care for this group of young people is critically important."

"Targeted consultation" will open until late in January 2025.

Other steps already underway included updated clinical guidelines on puberty blockers and plans for better monitoring of usage, and the Ministry of Health will also commission research to determine the long-term clinical and mental health and wellbeing impacts of puberty blockers.

Doctors react

A doctor providing gender care, Dr Massimo Giola, said the ministry's position was "reasonable", and would not change the way in which he practised.

"In my opinion, gender care should always be delivered in a multi-disciplinary context, combining relevant medical and mental health professional profiles - this is how I do gender care myself - and obviously caution should be exercised in prescribing, as in any other case.

"I think it is a well-balanced position and does not affect the way gender care is and should be delivered."

Auckland University paediatric endocrinologist Professor Paul Hofman said the ministry had "appropriately concluded" there was a lack of good quality evidence - but he stressed that what evidence was available indicated use of puberty blockers was "safe".

He supported the recommendation that prescribing should be done only by clinicians experienced in providing gender-affirming care, who were part of a wider multi-disciplinary team including psychological and mental health support.

"This is a very reasonable approach to an area where there remains substantive controversy," said Hofman, who was an independent reviewer for an earlier draft of the evidence brief.

"Encouragingly, the evidence published to date, while of low quality, all indicates the use of pubertal blockers is safe."

The effectiveness of treatment varied between studies, which partly reflected differences in selection of patients, he noted.

"At an individual level there are clear reports of improvement and it would be inappropriate to withdraw the use of this medication for the (likely many) patients suffering from gender dysphoria where it could improve mental health.

"However, a more evidence-based, multi-disciplinary team approach is a sensible precautionary suggestion to ensure therapy is focused on those where benefit is likely. Moreover, such teams need to follow up these patients to ensure there is ongoing support and benefit from the therapy."

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