Home > News > Details published about the research trial into puberty blockers for trans children and young people
25 November 2025 | News
Over the weekend, details were provided about the new research trial for prescribing puberty blockers to trans children and young people. Taking part in this research will be the only way to access puberty blockers on the NHS.
The full details of the research protocol can be found here: PATHWAYS TRIAL | King’s College London
TransActual have produced a summary, aimed at helping young people themselves understand the protocol, which is extremely helpful for understanding the details. You can read that here: The PATHWAYS Trial research protocol: key info – TransActual
This research trial has been developed in the context of the Cass Review into NHS England gender identity services for trans and gender questioning children and young people, which claimed that there was not high enough quality evidence of the efficacy and safety of puberty blockers for their regular use as a medical treatment for children and young people with gender incongruence outside of a research trial. This meant that a pause was placed on the prescription of puberty blockers by the NHS for this purpose across the UK. This happened in Scotland in April 2024.
We explained at the time that the Cass Review was published that we felt that the conclusions it had reached were hugely influenced by a view that the best outcome for a child or young person was that they not transition. We think that this is wrong. The best outcome for any child or young person is totally personal to them – for some that will be transition, and for others it won’t be. But if services are designed to see transition as a bad outcome, then this will inevitably lead to health care that cannot meet the needs of those people for whom transitioning is the only way for them to live happy, healthy lives.
The trial is UK-wide, and the Scottish Government have previously confirmed that NHS Scotland will work with the research team to ensure that Scottish children and young people are able to take part.
We think there is some significant uncertainties about how this might work in practice. The Scottish Government announced that new children and young people’s gender identity services would be designed and developed in September 2024, to eventually replace the current single national service provided by the Sandyford. However those new services are still in development, and there is no clear timetable for when that work will be completed. There will then be a further delay between agreement being reached on what new services should look like, and those being implemented across the country.
In the meantime, the current Children and Young People’s service is struggling to meet the needs of patients. There are around 900 patients on the waiting list, and last year the service offered less than five new appointments. This makes it very unclear whether or not there is currently capacity within Scottish services to ensure that trans children and young people can take part in the trial.
We are going to try and find out more about this as soon as we can.
We continue to be extremely concerned that the totality of evidence from around the world on the safety and efficacy of puberty blockers is not being used to inform decision-making by NHS Scotland (or indeed the NHS in other parts of the UK).
A range of countries have examined the evidence base for puberty blockers, either at a similar time or since the Cass Review and have come to very different conclusions about their use. They continue to be prescribed to trans children and young people where appropriate by national health services in other countries. Examples of this include:
Germany, Austria and Switzerland (June 2025): “A recommendation for puberty blockade in adolescents with gender incongruence or gender dysphoria should be determined in interdisciplinary cooperation. The prerequisite for this recommendation is a careful diagnostic assessment and clarification appropriate to the urgency and complexity of the individual situation by a mental health specialist experienced in the diagnosis and treatment of gender dysphoria in childhood and adolescence. The somatic part of the indication should be carried out by an experienced paediatric endocrinological specialist with regard to the prerequisites (pubertal maturity stage, absence of somatic contraindications, etc.).”
Poland (February 2025): “the complexity of the issues related to individuals at the developmental age excludes extreme solutions, such as access to medical interventions (e.g. gender-affirming hormonal interventions) without adequate assessment and preparation as well as arbitrary and complete denial of the inclusion of these interventions. The need for individualised care is also crucial;” (p. 2)
https://journals.viamedica.pl/endokrynologia_polska/article/view/104289
France (November 2024) “In adolescents that experience gender incongruence, the development of physiological pubertal characteristics can lead to increased distress, which may result in anxiety-depressive disorders, an alteration of psychological functioning sometimes complicated by self-harming or even suicidal behavior, leading to isolation and/or dropping out of school. Since the mid-1990s, treatment with GnRH analogues (GnRHa) has been proposed to prevent further pubertal development and reduce these risks. It has become common clinical practice as a first step in medical treatment of transgender adolescents.
We recommend that puberty suppression be offered by a multidisciplinary team or network trained in supporting transgender adolescents.”
https://www.sciencedirect.com/science/article/pii/S0929693X24001763#sec0009
New South Wales (February 2024): “These medications can delay the physical changes of puberty, giving young people more time to explore their gender identity without the added stress of unwanted changes to their body. The research shows that these medications are safe and work well to delay puberty, and their effects can be reversed if stopped. Some studies also suggest that this treatment can help reduce the distress young people with gender dysphoria feel during puberty. However, these medications might decrease bone strength, so doctors need to monitor this during treatment.”
This raises significant questions about whether it is ethical to withhold this treatment from children and young people in the UK, and whether requiring them to be part of a research trial to access this treatment really allows them to meaningfully consent to being participants in the research.
The maximum number of people who will be prescribed puberty blockers through the trial is 226. This is across the whole of the UK. To be eligible for the trial, a young person must have the capacity to consent to take part, have the agreement of at least one parent, carer or guardian to take part, and for a specialist at a gender identity service to believe that the prescription of puberty blockers is in their best interests (along with some further criteria outlined in the links above).
There are around 900 children and young people on the waiting list in Scotland alone (of course, not all of these children and young people will either want puberty blockers and/or a clinician may not judge it to be in their best interests). But given these numbers, this would seem to raise the very real possibility that there will be situations where clinicians, a young person themselves, and at least one of their parents, carers or guardians – everyone with the knowledge and expertise to make this decision – all agree that this is the right course of treatment, but that puberty blockers will still not be available to them. We are extremely concerned about this and cannot see how it is in children and young people’s best interests. We think that any child or young person who meets the trial’s criteria, and who clinicians think would benefit from puberty blockers and should take part in the trial, should be able to do so.
Here’s some other reactions to the research trial that we’re aware of:
TransActual: TransActual statement on launch of puberty blocker trial – TransActual
Mermaids: https://mermaidsuk.org.uk/news/research-protocol-puberty-blocker-trial/
30 Bernard Street Edinburgh EH6 6PR
+44 (0)131 467 6039 info@scottishtrans.org
Scottish Trans is part of the Equality Network
Scottish Trans is the Equality Network project to improve gender identity and gender reassignment equality, rights and inclusion in Scotland. The Equality Network is a leading Scottish lesbian, gay, bisexual, transgender and intersex (LGBTI) equality and human rights charity.
The Equality Network is a registered Scottish charity: SC037852, and a company limited by guarantee: SC220213.
We are grateful for funding from the Scottish Government
