Puberty Blockers – What are they, and why are they banned?

On the 27th of August, a ban on the sale and supply of puberty blockers, or puberty suppressing hormones, came into affect in Northern Ireland. This ban was initially passed in the rest of the UK during the election by Victoria Atkins, the previous Conservative Secretary of State for Health and Social Care, and was renewed by the current Labour Health Secretary, Wes Streeting. The temporary ban prohibits the sale or supply of puberty blockers specifically to treat gender dysphoria/gender incongruence in under-18s for the next three months and is due to expire on the 27th of November.

First thing’s first: what are ‘puberty blockers’?

Puberty blockers, or Gonadotropin-Releasing Hormone analogues (GnRHa), are a form of medication which suppresses your body’s natural hormone production. It works by releasing a steady dose of gonadotropin, a naturally occurring hormone within the body, sending a signal to the ovaries or testes to stop producing estrogen or testosterone. This kind of medicine has been in use for over three decades, and is typically prescribed to treat a wide variety of conditions including precocious (early) puberty, endometriosis, certain types of cancers, and various other hormone-related conditions.For around the past twenty years, it has also been used in gender affirming care for trans and gender diverse young people, specifically to suppress or pause the onset of natural puberty. Depending on when puberty blockers are prescribed, they may be used to provide a young person who is questioning their gender with the time and space to explore those feelings, without the added pressure of the changes incurred by natural puberty. Later on in transition, they may also be used in conjunction with Hormone Replacement Therapy (HRT) to both suppress the production of the hormone associated with an individual’s assigned sex and replace it with the desired hormone.

What does the ban cover?

The ban explicitly forbids the sale or supply of GnRHa to under-18s for the purposes of treating gender dysphoria/gender incongruence. The temporary ban was specifically written to target private prescriptions of puberty blockers, and as such those who are receiving puberty blockers through the Knowing Our Identity (KOI) clinic should continue to receive them. There are a number of exceptions to the ban, including:

• Any and all prescriptions received through NHS providers;
• Prescriptions from a UK-registered private provider dated before the 27th of August, or repeat prescriptions from a UK-registered prescriber where the original prescription was written in the six months prior to the 27th of August 2024;
• Prescriptions of GnRH to over-18s, and;
• Prescriptions for a purpose other than the treatment of gender dysphoria/gender incongruence.

Why were puberty blockers banned?

In short, the Cass Review. The evidence-basis for the banning of GnRHa relies almost entirely on the final Cass Report, which outlined her view that the prescription of this medication in transgender young people relies on a ‘low-quality evidence basis’.Irrespective of the variety of views around puberty blockers, the final Cass Report and accompanying evidence/literature reviews are far from the accepted or consensus view of gender affirming care for young people, and have been critiqued internationally by academics, professional associations and medical bodies.The Yale School of Law’s ‘Evidence-Based Critique of “The Cass Review”’ concluded:“Far from evaluating the evidence in a neutral and scientifically valid manner, the Review obscures key findings, misrepresents its own data, and is rife with misapplications of the scientific method. The Review deeply considers the possibility of gender-affirming interventions being given to someone who is not transgender, but without reciprocal consideration for transgender youth who undergo permanent, distressing physical changes when they do not receive timely care.” The University of York literature review, which has been heavily relied on to suggest that there is a limited amount of high-quality evidence on the efficacy of using puberty blockers in the course of treating gender dysphoria/incongruence, has been specifically critiqued alongside the wider Review. A group of academics and researchers from universities across the UK and Ireland stated in their paper “Critically Appraising the Cass Review”: “[W]e identified a high risk of bias in each of the systematic reviews driven by unexplained protocol deviations, ambiguous eligibility criteria, inadequate study identification, and the failure to integrate consideration of these limitations into the conclusions derived from the evidence syntheses. We also identified potential sources of bias and unsubstantiated claims in the primary research that suggest a double standard in the quality of evidence produced for the Cass Report compared to quality appraisal in the systematic reviews.”The Sax Institute in Australia, on direction from the New South Wales gender services, conducted two evidence reviews of research assessing the efficacy and safety of GnRH analogues for the treatment of gender dysphoria in 2020 and 2024. This was partially in response to the commissioning of the Cass Review and the publication of its Interim Report, which led to NHS England ceasing prescriptions of GnRHa in the treatment of gender dysphoria/incongruence. The most recent evidence check in 2024 stated: “Broadly, the newly identified evidence reinforced the finding of the previous Evidence Check regarding benefits and effectiveness. That is, PS agents (generally referred to as GnRHa) were reported to be safe, effective and reversible.”Both the European and the World Professional Associations for Transgender Healthcare (EPATH and WPATH), professional associations comprising of hundreds of clinicians and researchers working in gender affirming care across the world, have further critiqued the Cass Review. The WPATH Standards of Care (8th Edition) recognises the shortcomings of the existing evidence basis for gender affirming care, but comes to different conclusions about its delivery:“Although the existing samples reported on relatively small groups of youth and the time to follow-up varied across studies, this emerging evidence base indicates a general improvement in the lives of transgender adolescents who, following careful and comprehensive assessment, receive medically necessary gender-affirming medical treatment. Further, rates of reported regret during the study monitoring periods are low. Taken as a whole, the data show early medical intervention – as part of broader combined assessment and treatment approaches focused on gender dysphoria and general well-being – can be effective and helpful for many transgender adolescents seeking these treatments.”While it is widely accepted that more high quality research should be funded and conducted on the care given to trans and gender diverse youth, the benefits and potential side effects of puberty suppressants are well documented, and passing arbitrary bans on this medication is not the means by which better care outcomes are achieved. LGBTQIA+ and trans organisations have been advocating for increased funding for this research for many years, given the often poor quality care that many trans adolescents receive, particularly within the context of Northern Ireland. If the concern is the safety and health of trans and gender diverse adolescents, it is unconscionable to use the historical lack of investment in research on gender affirming care as an excuse to completely shut down or limit access to what has been described by many trans individuals who have grown into happy and healthy adults, and their families, as lifesaving care. It is worth noting that, while urging caution, the Cass Review does not recommend a ban on puberty suppressants. It also does recommend a variety of other actions: commissioning new, decentralised and locally available services for adolescents; providing holistic care and support to young people with gender dysphoria/incongruence; reducing waiting times for accessing care; and ensuring other services, such as the Child and Adolescent Mental Health Service, are capable of supporting trans and gender diverse young people in the interim period before accessing care. At present, none of these actions are being undertaken within the Northern Ireland context, and no mitigations have been put in place to reduce the impact of this seismic policy change on an extremely vulnerable and at-risk group.

Are puberty blockers ‘experimental’?

As explored above, these medications have been in use for around the past three decades, not just in gender affirming care but across a wide range of conditions and throughout a range of ages. While there are certain things that could be explored or researched further, they certainly aren’t experimental, and have a well-documented history of their use and their efficacy.Often, the argument that puberty suppressants are ‘experimental’ is informed by the fact that they are prescribed ‘off-label’ in gender affirming care. This means that they have been licensed and deemed safe for use in treating other conditions such as precocious puberty, but are used in the treatment of gender dysphoria without being specifically licensed for that purpose. This isn’t anything out of the ordinary: ‘off-label’ medications are used in a wide range of healthcare settings and are endorsed by the British Association of Psychopharmacology:

Health-care professionals have a responsibility to prescribe the most effective and safe treatments for their patients. For children and adolescents, this may mean choosing an off-label medication in preference to a licensed one, a non-pharmacological treatment or no treatment at all. The purpose of off-label use is to benefit the individual patient. Practitioners use their professional judgment to determine these uses. As such, the term off-label does not imply an improper, illegal, contraindicated or investigational use.

There is also a range of research exploring the efficacy of these medications, including specifically in treatment of gender dysphoria/gender incongruence. Several studies conducted in the Netherlands over the past decade or so have longitudinally explored the impact of prescriptions of puberty blockers on mental health and wellbeing, finding statistically significant improvements in both. “Puberty suppression in adolescents with gender identity disorder” (De Vries et al, 2011), “Young adult psychological outcome after puberty suppression and gender reassignment” (De Vries et al, 2014), and “Psychological functioning in transgender adolescents before and after gender-affirmative care compared with cisgender general population peers” (van der Miesen et al, 2020) found in their review of Dutch gender affirming care practices that this treatment pathway improves the functioning and mental wellbeing of trans and gender diverse youth.While acknowledging that more research can and should be done to ensure safety and efficacy, the vast majority of available evidence suggests that puberty suppressants are safe, effective and reversible, with limited negative side effects which can be easily monitored and managed. Research has been conducted over the course of the past few decades of regular use of GnRHa, exploring the impact it has on bone mineral density (BMD) and other factors in young people with central precocious puberty (CPP), with most demonstrating limited negative impact on both BMD and general reproductive function. Some clinicians working in gender affirming services around the world, including from the Royal Australian College of General Practitioners, have spoken out against the banning of this care. The RACGP Specific Interests Transgender and Gender-Diverse Healthcare Chair, Dr Michelle Dutton, said:“Trans healthcare research was not given the funding it deserved until relatively recently, [and] to then use this as a reason to deny trans people access to certain treatments is cruel and unethical.“We can help guide people in decision making where uncertainty exists without denying treatment altogether, and we can do this while continuing to gather data to inform future shared decision making – it cannot and should not be one or the other.”

So what happens next?

The puberty blocker ban is set to expire on the 27th of November unless renewed or translated to a permanent ban. The Department for Health and Social Care, alongside the Department for Health in Northern Ireland, conducted an invite-only consultation with trans and LGBTQIA+ community groups, clinicians, and others involved in the delivery of care, which ended on the 8th of October. Alongside colleagues in Mermaids NI, HereNI, the Belfast Trans Resource Centre, and Cara-Friend, we submitted a joint sector response to this consultation, and will share this response on this page once they are published by the Department.Regardless of the decision taken by Wes Streeting, the UK Secretary of State for Health and Social Care, Northern Ireland can take a different approach, and Minister Mike Nesbitt and the whole Executive are entitled to take their own view on whether or not to ban puberty suppressants. It is our view that they should not, and we would encourage members of the community – particularly those who are directly affected by this decision – to write to their MLAs and encourage them to take a strong position in favour of compassionate, evidence-based care.If you wish to read more about the situation for gender affirming care in Northern Ireland, you can read our latest article in the GNI Mag, and for advice on where to go for support, check out our page on public and private pathways to accessing gender affirming care.