The United Kingdom will spend $13.9 million to study the impacts of puberty blockers on minors experiencing gender-related distress. The U.K.’s National Health Service earlier this month announced its plan to invest in much-anticipated research into the controversial treatments, for which there remains insufficient data, per an NHS-commissioned report called the Cass Review. The study still needs to pass muster with an NHS ethics board.
The stakes of Britain’s study have only intensified following PresidentTrump’s return to power, which poses an existential threat to the American branch of pediatric gender medicine, a beleaguered field that provides medical treatments and surgeries to minors to change their sex characteristics. Advocates of the treatments refer to these interventions as gender-affirming care, while the White House, in a recent executive order, labeled them as “chemical and surgical mutilation.”
The executive order from President Trump seeks to block federal funds from flowing to hospitals that provide puberty blockers, cross-sex hormones, and gender-transition surgeries to gender-distressed patients under age 19. This comes as a slim majority of U.S. states — almost all of the conservative-leaning “Red states” — have passed restrictions or, in most cases, outright bans on medical gender treatments and surgeries for minors.
If Mr. Trump’s order were to survive judicial scrutiny, it could all but end American research into these medical interventions. A U.S. District Court judge in Maryland on March 4 issued a preliminary injunction against it.
Dr. Helen Webberley. BBC
The announcement of the U.K. trial’s funding has been a welcome development to many British families with children who struggle with their gender identity. Some advocates of child gender treatments, however, wish the British government would go even further.
“I wish I was reading the headline, ‘Ten million pounds funding for transgender children who have been desperately waiting for essential NHS care but have been left in limbo since the Cass Review,’” Dr. Helen Webberley said in a statement to the Sun. She is director of Gender GP, a controversial clinic that has prescribed gender-transition drugs to minors in the UK from abroad — leveraging legal loopholes Parliament has sought to close.
The NHS’s funding declaration comes nearly a year after the publication of a mammoth report the U.K. health authority commissioned, called the Cass Review, which was directed by renowned pediatrician Dr. Hilary Cass and which found that pediatric gender medicine is based on “remarkably weak evidence.” In response, the NHS barred physicians from prescribing puberty blockers or cross-sex hormones to treat gender-related distress in youths under age 16. The new study could potentially lead to restoring access to those treatments, depending on its findings.
In interviews with the Sun, some experts questioned the ethics of conducting any study of gender-transition drugs among children at this time. Or they expressed concern that the study’s ultimate design would only render more low-quality, unreliable evidence. These skeptics pointed to unknowns about puberty blockers’ neuropsychiatric impacts on adolescents. They cited the lack of assessment mechanisms to discern which gender-distressed children are most likely to maintain a lifelong transgender identity.
“It might be premature to conduct trials” of puberty blockers, said Mikael Landén, a researcher at the Karolinska Institutet in Sweden. Alluding to how much larger and more diverse the trans-identifying population of young people is today compared when this medical field was first established in the 1990s and 2000s, he said, “We first need to know the natural course of gender dysphoria in the different subgroups: those with childhood onset that worsens during puberty, those with later onset, those with comorbid psychological conditions, etc.”
The Cass Review, published by pediatrician, Dr. Hilary Cass, calls for gender services for young people to match the standards of other care in the UK. BBC
Dr. Landén led a systematic literature review — the gold standard of scientific evidence — of gender-transition treatment for minors. Like a half-dozen other such reviews, Dr. Landén’s review, published in 2023, found that the supporting research produced weak and unreliable conclusions. This prompted Sweden to become one of what is now a group of five European nations, including the U.K., in which national health authorities have reclassified these medical interventions as experimental and, accordingly, sharply restricted minors’ access to them.
The NHS has tapped Emily Simonoff, a professor of child and adolescent psychiatry at King’s College London, as director of the forthcoming puberty blocker study. She did not respond to a request for comment.
Attorneys representing Keira Bell — a British-American who sued the NHS in 2020, claiming she was harmed by gender-transition treatment she received in England at age 16 — threatened last month to sue to stop the puberty blocker study.
The U.K. health authority’s release regarding the forthcoming study states that “we don’t know” whether puberty blockers “are safe and helpful for young people” who have what is known as gender incongruence. This is a condition where an individual’s perceived gender is different from their sex. Gender dysphoria is distress stemming from the incongruence.
The NHS acknowledgement that it doesn’t know if puberty blockers are safe stands in contrast to the endorsements by most major U.S. medical groups of these medical interventions. Many leaders in this medical field assert that prescribing puberty blockers and cross-sex hormones to minors is safe and effective at treating their gender-related distress and easing anxiety, depression and suicidality.
Dr. Emily Simonoff. YouTube
A cadre of evidence-based medicine experts have called for a randomized trial of such drugs in hopes of producing more reliable research findings. For now, though, it remains unclear whether the new puberty-blocker study will indeed follow that format, or, like all other cohort studies of these drugs, will only be observational.
The study will be open to all youth attending UK gender clinics, according to the NHS. The study, the health authority states, “will track young people’s physical, social and emotional well-being, and the care and support they receive over time.” Youth put on puberty blockers will each be followed for two years and will undergo assessments of their cognition and brain development, such as through “paper-and-pencil” tests and and brain scans.
“The study will be overseen by independent advisory groups and will be subject to rigorous and regulatory checks by UK regulators and the NHS ethics committee,” the release states.
It remains unclear when the study will start — although it is slated to end in January 2031 — and whether the NHS will subsequently launch a linked study of cross-sex hormones that those in the puberty blocker study could ultimately transfer into.
In 2011, the NHS’s pediatric gender clinic, called the Gender Identity Development Service and centered in London, first adopted the gender-transition treatment model, called the Dutch protocol, that was pioneered by researchers in the Netherlands starting in the mid-1990s. In more recent years, whistleblowers began reporting that GIDS provided shoddy and ideologically-driven care that was too narrowly focused on gender identity. Immediately following the Cass Review’s publication, the NHS shut down the clinic.
Dr. Anna Hutchinson. YouTube
The NHS’s adult gender clinics refused to share with the Cass Review team any data regarding former GIDS patients, even stripped of identifying markers. This left the review team unable to assess long-term outcomes among the approximately 9,000 children to have received care from GIDS. British investigative journalist Hannah Barnes estimated in her signature 2023 book on the clinic’s downfall, “Time to Think,” that approximately 2,000 of these young persons received puberty blockers.
In the vast majority of gender dysphoria cases, minors who start blockers go on to take cross-sex hormones, which cause various changes to secondary sex characteristics, some of which are irreversible. In an interview, Kenneth Zucker, a veteran psychologist in the pediatric gender field, argued the importance of the NHS conducting follow-up research of the former pediatric patients.
“That could teach us a lot, and probably way more than the new study will be able to teach us,” said Dr. Zucker, who lives in Toronto. But he acknowledged that such a pair of research efforts need not be mutually exclusive. He also pointed to a recent editorial by Ms. Barnes in the New Statesman in which she argued that the new puberty blocker study “is expensive and adds little” to existing knowledge.
Since shuttering GIDS, the NHS has begun opening a network of smaller, local gender clinics for youths throughout the UK. These clinics are meant to provide holistic psychological support for children and adolescents with gender dysphoria. This population has a particularly high rate of mental-health diagnoses, self-harm, suicidality, and autism, especially compared with gender dysphoric children in previous generations.
President Trump signing executive orders in the Oval Office. Alex Wong/Getty Images
In June, the UK’s outgoing conservative government implemented a ban on private clinics prescribing puberty blockers to youths outside of a clinical trial. Most Britons receive their medical care from the NHS. The Labour Party has since made the ban permanent, with political leaders voicing concern about puberty blockers’ safety.
Dr. Zucker expressed concern that, given it has become much more common for pre-adolescent children with gender dysphoria to socially transition, meaning to present publicly as the opposite sex, the current lack of availability of puberty blockers in the UK could set them up for a much more severe collision course with their ultimate natural puberty. He said that the NHS is “missing an important piece of the pie” if they don’t also research the needs and gender-identity trajectories of these young children.
British politicians’ largely bipartisan consensus on restricting puberty-blocker access contrasts markedly with the fractious political landscape on this issue in America. Democrats have, with a few notable exceptions, sought to defend youth access to these medical interventions. Republicans have increasingly made eliminating the entire field of pediatric gender medicine a central party platform.
President Trump, in his address to Congress earlier this month, made a mockery of what he claimed was $8 million in federal grants going toward “making mice transgender.” This was actually a reference to National Institutes of Health–funded studies that use animal models to study the impacts of cross-sex hormones.
The following day, Elon Musk’s DOGE operation announced on social media that it had axed seven such grants, specifying two in particular that totaled $565,000. The Chronicle of Higher Education and Nature have each reported that the NIH has been canceling numerous grants related to transgender people. The Trump administration’s recent effort to cancel $400 million in grants to Columbia University has also hit research considering the transgender population.
Dr. Kenneth Zucker. Facebook
Recent surveys have found that the vast majority of Americans, including most Democrats, are opposed to pediatric access to gender-transition interventions. Democratic politicians, however, have largely accommodated the party’s vocal progressive wing and well-organized transgender rights activists.
The associated American political battles have escalated in tandem with a surge in transgender identification in young people in the U.S. and across the Western world.
A study published in January found that gender dysphoria diagnoses surged by 50-fold among English youths attending primary care practices between 2011 and 2021. By the end of this period, 0.4 percent of such 17-year-olds had the diagnosis in their chart.
Research has recently identified similar trends in America. Since about 2014, gender dysphoria diagnoses have increased dramatically among adolescents and young adults — especially natal females — according to multiple studies, while remaining largely stable among those born before the mid-1980s. Another study, published in January, found that between 2018 and 2022, about one in 1,000 privately insured 17-year-old Americans were taking cross-sex hormones; the rate is higher among biological girls receiving testosterone.
President Trump speaks with reporters as he signs executive orders in the Oval Office at the White House, February 10, 2025.
President Trump speaks with reporters as he signs executive orders in the Oval Office at the White House, February 10, 2025. AP/Alex Brandon
A previous NHS study found that puberty blockers were not associated with any significant psychological change among GIDS patients. The authors kept those disappointing findings under wraps for several years, until their existence was uncovered by University of Oxford sociologist Michael Biggs; the GIDS team finally published their results in 2021.
In recent months, American researchers who have previously touted puberty blockers as a discrete and beneficial intervention have begun to argue, instead, that this medical intervention should be considered part and parcel with cross-sex hormones. In an amicus brief submitted to the Supreme Court in September over the pending case concerning Tennessee’s ban on pediatric gender-transition treatment, a team of physicians who oppose the ban argued that the Cass Review was wrong to analyze the use of these two drugs separately.
Skeptics of such treatment argue that puberty blockers do not provide the “time to think” that leaders in pediatric gender medicine say they do; rather, the skeptics assert, the drugs essentially lock in a transgender identity and are only seen by youth as a waystation before going on hormones.
Anna Hutchinson is a former GIDS psychologist turned whistleblower. In an interview, she effectively agreed with the amicus brief authors, saying, “If you’re really going to evaluate gender-affirming medical treatment, you’d have to evaluate the whole pathway.”
“The Dutch protocol is a three-stage process,” Dr. Hutchinson added, noting that gender-transition surgeries were the third step. “You’d never had puberty blocker as a stand-alone.”
Dr. Stephen Levine is a psychiatrist at Case Western Reserve University with extensive experience treating youth gender dysphoria. He has also served as a paid expert witness on behalf of statehouse bans of pediatric gender-transition treatment. (Multiple authors of the aforementioned amicus brief are themselves paid expert witnesses for the other side of this legal dispute — a fact that invariably goes unmentioned in the articles in liberal media outlets that have sought to discredit Dr. Levine and other paid experts on that side of these disputes.) Dr. Levine said that for the blockers study to achieve ethical balance, the researchers would need to be “agnostic about the best treatment,” lest they bias the results.
Dr. Webberley said essentially the opposite. She criticized the selection of Dr. Simonoff as principal investigator — given that, like Dr. Cass, the child psychiatrist appears to lack expertise in treating trans children. The NHS, however, apparently tapped Drs. Cass and Simonoff precisely because they did not have what are known as intellectual conflicts of interest from working in pediatric gender medicine.
The Gender GP director expressed concern that the NHS puberty-blocker research team would be biased against what she insisted was the already-proven safety and efficacy of these medical interventions.