Puberty blockers will not routinely be offered to children treated at new regional gender identity clinics in England, the NHS has confirmed.
New centres are expected to open later this year, in place of the London-based Gender Identity Development Service (GIDS) clinic.
It was announced last July that the capital's GIDS clinic would be shutting down.
Part of the regional network replacing it is expected to open in the autumn, with NHS England previously saying it cannot confirm when the GIDS clinic will shut as new regional services need to be ready to take on patients to ensure there is no gap in the provision of care.
NHS England Published Interim Service Specifications
On Friday, NHS England published an update following its previously stated intention to only commission puberty-supressing hormones as part of clinical research.
It said: "We are now going out to targeted stakeholder testing on an interim clinical commissioning policy proposing that, outside of a research setting, puberty suppressing hormones should not be routinely commissioned for children and adolescents who have gender incongruence/dysphoria."
A spokesman confirmed that children treated at the new gender clinics will not be routinely offered puberty blockers as part of their treatment, but said there could still be exceptional circumstances to that if a clinician makes the case that there are reasons why the child should have them.
Treatment being received by those attending the London GIDS clinic will not change, he added.
The NHS has previously acknowledged there had been a "lack of clinical consensus and polarised opinion on what the best model of care for children and young people experiencing gender incongruence and dysphoria should be".
An independent review, led by Dr Hilary Cass, was commissioned in September 2020 amid the rise in demand, long waiting times for assessments and "significant external scrutiny" around the London-based GIDS clinic's approach and capacity.
The NHS said it aims to have a study started by next year on the impact of puberty blockers on gender dysphoria in children and young people with early-onset gender dysphoria.
An NHS spokesperson said: "The NHS is today publishing an interim specification for gender services for children and young people in line with advice and recommendations from the Independent Cass Review – this will allow the new centres to finalise their preparation for service provision later this year.
"The NHS is now engaging on the proposal that puberty blockers will not be made routinely available outside of research. We will develop a study into the impact of puberty blockers on gender dysphoria in children and young people with early-onset gender dysphoria, which aims to be up and running in 2024."