![\"\"](\"https:\/\/www.newsbeep.com\/uk\/wp-content\/uploads\/2026\/01\/gender-1038x778.jpg\")
\n Illustration by
\nGary Waters \/ Ikon Images<\/p>\n
\n Illustration by
\nGary Waters \/ Ikon Images<\/p>\n
Patient information sheets given to parents<\/a> and children<\/a> who are considering participating in an NHS-backed puberty blocker trial do not provide a clear or accurate account of the balance of risks and benefits of puberty suppression, a group of healthcare professionals argue.<\/p>\n The Clinical Advisory Network on Sex and Gender (CAN-SG) \u2013 a coalition of more than 100 clinicians and medics \u2013 contends that without this type of evidence-based guidance on the risks of involvement, parents cannot provide truly informed consent, and that the children and young people in their care therefore should not assent to participation.<\/p>\n The new trial is part of a group of research projects called Pathways<\/a> (Puberty Suppression and Transitional Healthcare with Adaptive Youth Services) aiming to provide high-quality evidence to help inform and improve the care given to children and young people attending NHS gender services. It\u2019s run by a team at King\u2019s College London (KCL), with the trial due to start this month (January). However, KCL has confirmed to the New Statesman that recruitment to the trial has not yet begun.<\/p>\n A clinical trial of puberty blockers was one of 32 recommendations made by Hilary Cass in an independent review of NHS children\u2019s gender services. But ever since a new trial was confirmed in November 2025, debate over whether it is ethical to begin another study of puberty blockers has been fierce.<\/p>\n New year, new read. Save 40% off an annual subscription this January.<\/p>\n Public opinion appears to be against it. Polling by Whitestone Insight<\/a> showed the majority of adults were not in favour, including among both current Labour supporters and those who voted for the party in the 2024. The government faces a legal threat<\/a> calling for the trial to be stopped.<\/p>\n More than 380 clinicians, including some who specialise in evidence-based medicine and have helped write national clinical guidelines, have written<\/a> to the Health Secretary Wes Streeting expressing their disagreement that the trial should take place in its current guise, or before other less invasive research avenues have been pursued first. The signatories, which include 220 doctors and surgeons, expressed \u201cgrave disquiet\u201d.<\/p>\n Some are experts in trial design who are critical of this particular trial\u2019s approach. Others believe no trial could be ethical, among them clinicians who worked with children at <\/a>Tavistock\u2019s Gender Identity Development Service (Gids<\/a>), which closed in March 2024.<\/p>\n Now, some of these professionals are raising alarm over the patient information sheets given to parents and children. The sheets are meant to provide detailed information about the potential risks and benefits to participants in any medical trial.<\/p>\n Speaking in committee room 3 of the House of Lords on 15 January, Dr Louise Irvine, co-chair of CAN-SG, told gathered journalists: \u201cParents have not been told the true likelihood or the full scope of the harms involved.\u201d<\/p>\n Nowhere are parents told of the possibility that their children might feel differently about their gender identity in the future, that there is no reliable predictor of which children might benefit from pubertal suppression, or that they could possibly regret medical steps taken when they were younger. Irvine argued that risks to bone health, sexual function, brain maturation, identity development and fertility were also not adequately reflected in the information sheets.<\/p>\n \u201cThe Pathways Patient Information Sheets treat puberty blockers as though they were a standalone, reversible pause,\u201d Irvine argued. This characterisation was \u201cmisleading\u201d, she added. \u201cIn reality, more than 90 per cent of children who start puberty blockers go on to cross sex hormones.\u201d She urged the press to read them for themselves. The New Statesman has done so.<\/p>\n Cass has publicly supported the Pathways trial, saying in November she was \u201creally pleased\u201d the trial was going ahead. \u201cGiven that there are clinicians, children and families who believe passionately in the beneficial effects [of puberty blockers],\u201d she said, \u201ca trial was the only way forward to make sense of this.\u201d Yet those concerned about it cite the findings of Cass and her team\u2019s review as reasons to be cautious about the trial. This publication did the same in its detailed analysis<\/a> of the trial\u2019s design and stated aims.<\/p>\n The trial information sheets say that puberty blockers may provide young people with gender incongruence \u201ctime to explore their gender identity without worrying about their body starting to change<\/a>\u201d. Parents and children are not told how speculative this hypothesis is, nor that it was rejected by the Cass Review. \u201cGiven that the vast majority of young people started on puberty blockers proceed from puberty blockers to masculinising [or] feminising hormones, there is no evidence that puberty blockers buy time to think, and some concern that they may change the trajectory of psychosexual and gender identity development,\u201d Cass wrote in the 2024 review.<\/p>\n One study<\/a>, started by the Tavistock Gids and University College London Hospitals in 2011, found that 98 per cent (43 out of 44) of children aged 12-15 taking part progressed from puberty blockers to start cross-sex hormones (testosterone for females wishing to masculinise and oestrogen for males wanting to feminise). Gids staff working with gender-distressed children were presented with similar statistics in 2016. One, Dr Anna Hutchinson, described it as her \u201choly fuck\u201d moment<\/a>. And a wake-up call for many of her colleagues too.<\/p>\n Back then, clinicians saw that this data had profound implications for consent. It wasn\u2019t just that families and young people needed to be told about blockers: they also needed more information on what transition might entail. \u201cYou couldn\u2019t do it after you put them on the blockers,\u201d Dr Natasha Prescott told me while I wrote Time to Think, \u201cyou had to do it before.\u201d Because \u201conce they\u2019re on the blocker, they\u2019ve started along a path\u201d.<\/p>\n In later years, a group of independent health professionals \u2013 brought in to provide additional oversight of Gids\u2019 puberty blocker referrals \u2013 insisted children could not begin treatment without the expectation of progression to hormones being \u201cadequately discussed and understood<\/a>\u201d. This \u201cMulti-Professional Review Group\u201d (MPRG) was introduced in 2021, following NHS England and Care Quality Commission concerns about Gids.<\/p>\n Perhaps most striking in today\u2019s context is that the Health Research Authority (HRA) \u2013 the body responsible for ensuring the quality of the patient information sheets \u2013 has itself previously warned against describing puberty blockers as providing \u201cbreathing space\u201d. In its 2019 investigation into the <\/a>Gids early intervention study<\/a>, the HRA advised staff working in gender clinics to \u201cavoid referring to puberty suppression as providing a \u2018breathing space\u2019, to avoid risk of misunderstanding\u201d. Instead, the investigation argued, they should be seen as an aid to future medical transition.<\/p>\n The children taking part in the 2011 Gids study had been \u201ccarefully selected\u201d, chosen because of their long-standing distress around their gender identity, the HRA noted. The new Pathways trial similarly claims that only a small minority of children with both a stable gender identity and home life, and who clinicians believe will \u201cbenefit<\/a>\u201d from puberty blockers, will be eligible to take part. It\u2019s unclear, therefore, why the same HRA rationale would not apply equally to the new research.<\/p>\n Parents who have already faced the difficult decision over whether to agree to their distressed children\u2019s puberty being blocked are raising similar concerns. The New Statesman has seen a lengthy, forensic letter sent to the HRA on 15 January by a concerned clinician and researcher, who is a parent to a trans-identified child (who is not part of the Pathways trial). Having \u201cbeen faced with pressure to agree to such medication in a context of similar inadequate information\u201d, the sender explains they did not want others to do the same.<\/p>\n The letter, written with the help of \u201cseveral colleagues\u201d and now being handled as a formal complaint, claims not just that critical information is missing, but that the information sheets as currently written violate the HRA\u2019s own requirements. Any research involving the NHS must be approved via one of the HRA\u2019s independent Research Ethics Committees (REC). The REC is then responsible for granting both ethical approval for the trial as a whole, and for ensuring that information sheets allow for informed decision-making. HRA guidance states that in order to facilitate this, researchers \u201cmust state clearly what the risks and benefits of your study realistically are<\/a>\u201d.<\/p>\n The King\u2019s College London research team was questioned by the REC on 4 September 2025 on the effect of puberty blockers, as approval was sought for the Pathways trial. Might, the ethics committee asked, \u201cblocking the normal biological process of puberty via the study drug\u2026 change the participants views, or prevent further development of their views, on self-identity<\/a>\u201d? The research team responded that it was \u201cacutely aware of this\u201d. The researchers were advised to make the impact of the drug \u201cclear in the PIS [patient information sheet]\u201d. The information sheets do not reflect the risk that treatment with puberty blockers may in itself \u201clock-in<\/a>\u201d \u2013 to use Cass\u2019s term \u2013 children and young people to a pathway ending in medical transition.<\/p>\n Asked whether the patient information sheets allowed parents and children to make a truly informed decision, a spokesperson for the HRA, said: \u201cThe Pathways trial was reviewed in line with well-established legal and national policy frameworks by a properly constituted Research Ethics Committee (REC) for clinical trials.\u201d<\/p>\n There is an \u201cestablished and thorough process for how RECs review information for study participants\u201d, they continued, which ensures \u201cinformation provided is as clear as possible\u201d and key points are \u201ceasily understood\u201d. \u201cThis includes explaining potential risks and benefits that are relevant to the study in review. RECs cannot consider wider issues or concerns which are beyond the scope of the study being reviewed,\u201d they added.<\/p>\n There are multiple other weaknesses in the information provided to parents and children, concerned professionals represented by the CAN-SG maintain. According to Irvine, the information provided \u201cignores or minimises critically important risks identified in the Cass Review\u201d.<\/p>\n When Cass first recommended<\/a> research into puberty suppression for gender dysphoria in July 2022, for example, she warned of potential \u201clonger-term neuropsychological consequences\u201d with using the drugs. Brain maturation, she said \u201cmay be temporarily or permanently disrupted by puberty blockers, which could have significant impact on the ability to make complex risk-laden decisions\u201d. In the Pathways trial information sheets, that risk is represented like this: \u201cThere are also concerns that GnRHa [gonadotropin releasing hormone analogues, the puberty-suppressing treatment] might affect brain development and learning, based on findings from animal studies.\u201d<\/p>\n Risks to both bone health, which \u2013 according to academics undertaking a systemic review of all the evidence available<\/a> \u2013 is \u201ccompromised during puberty suppression<\/a>\u201d, and sexual function are not explored adequately in the patient information sheets either, Irvine said.<\/p>\n The KCL Pathways research team told the New Statesman the trial had gone through \u201cthe normal rigorous process of independent ethics scrutiny\u201d and that, \u201cin line with HRA standards on informing participants and seeking consent, our materials set out the study purpose, design and what is known and unknown about puberty\u2011suppressing treatment.\u201d<\/p>\n But it is the major risk to children\u2019s future fertility from puberty suppression, where there is perhaps the greatest mismatch between what is known and what is contained in the patient information sheets. And this is linked intrinsically to the fact that, as the 2011 study \u2013 and other international studies \u2013 suggested, almost all children move from puberty blockers to hormones.<\/p>\n In the 26-page information sheets, the risk to children\u2019s future fertility is mentioned across five lines. Parents of potential trial participants are told that \u201cit is important that your child talks to the doctors in the clinic about the options they have for their fertility in the future<\/a>\u201d. These include egg or sperm storage, the leaflet adds.<\/p>\n But there is no explicit explanation as to why this should be so. When the same drug planned for use in the trial is prescribed for precocious puberty (when children begin puberty too early at very young ages), the information leaflet<\/a> does not advise fertility preservation. The greatest risk to fertility from puberty blockers, when used in the very different context <\/a>of gender medicine, is brought about by the likely progression from blockers to hormones. When puberty is suppressed in the earliest stages, and then followed by masculinising or feminising hormones, there is no opportunity for children\u2019s eggs or sperm to mature. \u201cFor those children, fertility preservation would require stopping puberty blockers to allow gamete maturation for collection,\u201d Irvine explained.<\/p>\n Pathways researchers said that they would continue to keep participant information under review throughout the trial. \u201cBeyond the patient information leaflets,\u201d the team explained, \u201cthe young person and their parents\/legal guardians must be able to show that they fully understand the possible benefits, risks, and long-term effects of treatment. This understanding is developed through a series of detailed discussions with clinical specialists in the new gender services and those who have expertise in hormonal interventions.\u201d<\/p>\n Fertility preservation \u201cis presented in an unrealistically optimistic way\u201d, Irvine added. Even for children who had reached a later stage of puberty and had viable gametes to store before joining the trial, it remained an \u201cinvasive and difficult process\u201d, she said.<\/p>\n There is no data on what impact \u2013 if any \u2013 blocking puberty for several years into later adolescence might have on future fertility, should that young person choose not to take hormones. In part, this is because so few children have done this.<\/p>\n A Department of Health and Social Care spokesperson said that \u201cyoung people with gender incongruence need access to high-quality, safe and effective care\u201d and it was \u201cfollowing the Cass review, which was clear that the evidence on care for these children is lacking, and proposed this research to help provide it\u201d. The spokesperson said children received \u201ca range of guidance beyond these information sheets through detailed discussions and rigorous checks with clinicians over a number of months\u201d and this included conversation on detransition.<\/p>\n![](\"https:\/\/dl6pgk4f88hky.cloudfront.net\/2021\/09\/TNS_master_logo.svg\"){kind=logo}
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