A leading Oxford University academic has added his voice to a growing list of experts warning against puberty blockers for transgender children, saying they are harmful and part of a flawed approach to care.
Professor Ashley Grossman, an endocrinologist, says there is “no compelling evidence” to show that puberty blockers help trans children. She highlighted a new study that indicates they damage the testicles and sperm of boys who take them.
It raises questions about the “reversibility” of puberty blockers, a key claim by trans activists who promote the drugs and say they “pause” puberty and buy time for trans children to make decisions about their gender.
Grossman’s comments come ahead of the publication of the long-awaited Cass Review in the UK, which will confirm a shift from medicalised treatment of trans children to one based on support and psychotherapy.
Professor Ashley Grossman, an endocrinologist at the University of Oxford, says there is “no convincing evidence” to show that puberty blockers help trans children
Trans activists say puberty blockers and other gender-affirming care save lives among suicide-prone group
“Studies have shown that there is no compelling evidence for the routine use of puberty blockers,” Grossman said in a statement.
“In fact, there is some recent preliminary data (although not yet peer-reviewed or published) that suggests that some of its effects on the testes and sperm may not be reversible.”
Grossman said blockers may be “helpful” for some trans children, but that the drugs were too risky to distribute to the “very growing” number of young people who identify as trans today.
“Routine puberty blocking treatment for this use has not yet been adequately studied, and many of these children may have other problems for which they need help,” he added.
His comments point to one of the most controversial issues of our time: whether to provide medications and surgery to children experiencing gender confusion or “dysphoria” and ask their parents or doctors for help.
Puberty blockers were originally developed to suppress the hormones of minors who started puberty too early.
Today they are prescribed off-label to an increasing number of trans children.
Proponents of gender-affirming care, as it is known, say it saves lives for a suicide-prone group, and that puberty blockers help preteens “pause” their puberty and buy time to weigh decisions that They alter their lives.
Puberty Blocker Prescriptions Continue to Rise in the United States
Most children who are treated with puberty blockers go on to receive cross-sex hormones, like this patient at the Blue Mountain Clinic in Montana.
Critics warn about the growing number of young people who identify as trans and say puberty blockers, cross-sex hormones and surgeries are often unnecessary and probably dangerous when counseling gets better results.
Republican lawmakers have banned puberty blockers and other trans care for minors in nearly two dozen states.
Norway, Finland, Sweden, the Netherlands and the United Kingdom are among a growing list of European countries that have restricted or stopped trans interventions in children altogether.
Britain is preparing for the long-awaited publication of a review by leading consultant pediatrician Hilary Cass that will shape future NHS England care for trans children and young people, due on Wednesday.
Early reports suggest it will warn about a lack of data on the safety of trans hormones in children and propose a more holistic care package that assesses whether young patients suffer from mental health problems other than gender anxiety.
This puts Britain at odds with the influential American Academy of Pediatrics (AAP), which recently suggested that denying minors gender-affirming care is child abuse.
The leading US pediatric group said “withholding (gender-affirming care) is harmful to children and amounts to state-sanctioned medical neglect and emotional abuse.”
The AAP made this claim in a consensus statement released in late December, and the statement was in response to a wave of age restrictions on puberty-blocking medications and surgeries for children in red states.
While its opinions are not medically binding, the panel is made up of 70,000 of the country’s top children’s doctors and its recommendations are considered the gold standard.
Chloe Col, 19, who transitioned to male at 13 before regretting her decision at 16, is among a growing number of young people regretting their trans treatments and seeking to reverse them. She says she regrets taking puberty blockers when she was 13.
Puberty blockers are prescribed off-label to increasing numbers of trans children
Transgender activists responded angrily to the Cass Review’s direction.
They maintain that trans children are stigmatized and face abuse, and that many will take their own lives unless doctors give them hormones and surgeries that affirm the sex with which they identify.
“Trans kids face harm and injustice at every turn,” the TransSafetyNow account posted on X/Twitter.
“The Cass Review final report does nothing to help trans children live happy, healthy, safe and confident childhoods.”
A Mayo Clinic study published this month found that puberty blockers can cause shriveled testicles, fertility problems and even cancer among trans children who take them, in the latest study to raise alarm about transgender medicine.
They found that puberty blockers harm testicular development and sperm production in ways that are not completely reversible and could affect users’ ability to have children when they grow up.
33-page Mayo Clinic study revealed damage at the cellular level in puberty blockers
“At the tissue level, we observed mild to severe sex gland atrophy in children treated with puberty blockers,” geneticist Nagarajan Kannan and others wrote in the 33-page study.
“We provide unprecedented histological evidence revealing deleterious responses of pediatric testicular sex glands” to medications.
The researchers highlighted the case of a 12-year-old boy who had taken puberty blockers for 14 months.
Nearly 60 percent of their sex glands had “completely atrophied,” they said.
There was also an “emergence of microlithiasis,” or small clumps of calcium that are linked to testicular cancer.
In a 14-year-old patient who had been taking puberty blockers for four years, they found that his sperm-producing cells were atrophied.
Scientists at the world-famous clinic said the results were worrying but more research was needed.
Evidence of “sex gland atrophy and abnormalities of histological data raises potential concern regarding the complete ‘reversibility’ and reproductive fitness” of sperm in boys taking puberty blockers, he said.
The study came on the heels of the so-called ‘WPATH files’: leaked messages from the world’s leading body for gender-affirming care, which showed doctors behaving more like activists who were silent about the huge downsides of trans medicine.