Direct medical guidance was given by the doctor.

Since toddlerhood, Emma Basques has identified as a girl. A Phoenix doctor told her to take a drug to stop puberty.

Jacy Chavira was starting to believe she was a boy when she was 13 years old. She was told to use the drug and puberty would be stopped.

An 11-year-old in New York is depressed and wants to be a boy. The family was told the drug was the best option by a therapist.

The therapist said puberty blockers help kids like this. It was presented as a way to stop the bleeding.

puberty blockers are the first line of intervention for the youngest ones seeking medical treatment as the number of adolescents who identify as trans grows

They are often used to buy time to weigh a medical transition and avoid the anguish of growing into a body that feels wrong. High rates of depression and other mental health issues are suffered by trans adolescents. Some patients with gender Dysphoria have been alleviated by the drugs.

ImageEmma, now 14, has identified as a girl since toddlerhood and feels that she’s on the right path.
Emma, now 14, has identified as a girl since toddlerhood and feels that she’s on the right path.Credit...Verónica G. Cárdenas for The New York Times

Dr. Norman Spack, who pioneered the use of puberty blockers for trans youth in the United States, believes they can be lifesavers. Kids are being so relieved.

Concerns are growing among some medical professionals about the consequences of the drugs as an increasing number of adolescents identify as trans. The questions are sparking government reviews in Europe, prompting a push for more research and leading some prominent specialists to rethink at what age to prescribe them. Some doctors won't recommend them.

Doctors in the Netherlands first offered puberty blockers to adolescents three decades ago. Since then, the practice has spread to other countries, with differing protocols, little documentation of outcomes and no government approval of the drugs for that use.

According to reviews of scientific papers and interviews with more than 50 doctors and academic experts around the world, there is emerging evidence of potential harm from blocking drugs.

Megan TwoheyChristina JewettMegan Twohey and Christina JewettReporting for the Investigations Desk

The treatment of adolescents who identify as trans is causing a lot of confusion and controversy.

We interviewed doctors around the world and spoke to patients and family members.

There is a closer look at what we found.

Megan TwoheyChristina JewettMegan Twohey and Christina JewettReporting for the Investigations Desk

The use of puberty blockers is often described by doctors as a safe way to stop the puberty process.

The treatment is likened to child abuse by Republicans.

Megan TwoheyChristina JewettMegan Twohey and Christina JewettReporting for the Investigations Desk

There is limited research going on at the moment. Adolescents who feel they were born in the wrong body can be helped by the treatment. Doctors and patients said it was life-saving.

Potential long-term effects on patients' bones and brains were found to be emerging evidence.

Megan TwoheyChristina JewettMegan Twohey and Christina JewettReporting for the Investigations Desk

One of the biggest concerns about the drugs is the effect on bones.

There are concerns that adolescents could be locked into a path of medical intervention before they know who they are.

Megan TwoheyChristina JewettMegan Twohey and Christina JewettReporting for the Investigations Desk

The benefits of taking blockers far outweigh the risks according to patients and their families.

It can be hard to fully evaluate the decision because of the limited studies.

Megan TwoheyChristina JewettMegan Twohey and Christina JewettReporting for the Investigations Desk

Drugs suppress hormones that help develop the reproductive system but also affect bones, the brain and other parts of the body.

A lifetime of bone health is determined by the amount of bone mass. According to an analysis commissioned by The Times of observational studies, bone density growth flatlines when adolescents use blockers.

Jacy Chavira, 22, thinks puberty blockers were prescribed to her too quickly. After treatment with blockers starting at 13, followed by testosterone, she has resumed her female identity.Credit...Verónica G. Cárdenas for The New York Times

Doctors who treat trans patients think they will recover the loss when they stop using blockers. Two studies from the analysis that tracked trans patients bone strength while using blockers and through the first year of sex hormone treatment found that many do not fully rebound and lag behind their peers.

That could lead to a higher risk of broken bones for people in their 50s than for people in their 60s, and more harm for patients who start treatment with weak bones.

There will be a price for bone research, according to Dr. Sundeep Khosla. The price is likely to be a deficit in mass.

Many physicians in the United States and other countries are giving blockers to patients at the first stage of puberty, allowing them to progress to sex hormones as early as 12 or 13 years old. They believe starting treatment at a young age helps patients get better aligned with their gender identity and protects their bones.

Other doctors warn that life-changing choices could be made before patients know who they are. For some adolescents, puberty can help clarify their sex at birth and for others, it can help confirm their gender.

The most difficult question is whether puberty blockers give children and young people enough time to consider their options or whether they lock in children and young people to a treatment pathway.

“There’s going to be a price,” said Dr. Sundeep Khosla, who leads a bone research lab at the Mayo Clinic. “And the price is probably going to be some deficit in skeletal mass.”Credit...Jenn Ackerman for The New York Times

The National Health Service in England proposed to restrict use of the drugs for trans youths to research settings. The risk of blockers, the steep rise in young patients, the mental health issues that many exhibit, and the extent to which their mental health should be assessed are some of the issues that Sweden and Finland have placed limits on.

There is no universal policy in the US.

Republican governors and lawmakers in more than a dozen states are working to limit or even criminalize the treatments, as some in their party also seek to restrict access to sports and bathrooms. The Florida medical board banned the use of drugs and surgeries for patients under 18. The Biden administration says that it's a civil rights issue. Some advocates don't like people who question the treatments' safety.

More guidance could be provided by long-awaited research funded by the National Institute of Health. In 2015, four prominent American gender clinics were awarded $7 million to study the effects of blockers and hormone treatment on young people. The United States produced no data on the impact or safety of blockers for patients under the age of 12. They haven't reported key outcomes of their work yet, but they will soon.

The benefits of easing the despair of gender dysphoria far outweigh the risks of taking blockers, according to many young patients and their families. It can be difficult to fully evaluate a decision due to limited studies and politics. There wasn't much research into the long-term effects of the treatments examined.

After starting drugs three years ago, Emma Basques believes she is on the right path.

Jacy Chavira decided that the medical treatment was not appropriate for her and she became a woman.

The parents of a New York adolescent stopped using drugs after their child lost a lot of bone density.

The mother said that they went into this because of their desire to help. I worry that we got into a situation with a very powerful drug and don't know what the long term effects will be.

Emma’s mother, Cherise Basques, right, and father let her grow her hair longer and take other steps to socially transition when she was 5.Credit...Verónica G. Cárdenas for The New York Times

Cherise and Arick Basques realized that their toddler was different after a short time. The child preferred dresses, Barbie dolls and ballet over toys. The child yelled "No!" when Ms. Basques introduced her then-4-year-old as her son. I'm your daughter.

This was the first time that the couple had worked with children. The therapists the parents called didn't feel like they could help. The child's doctor only told them that things could change once the child started school. The couple found a support group for parents of trans children.

The child, who was 5 years old at the time, was allowed to use the name Emma, grow long hair and take other steps to socially transition. The doctor at the local gender clinic told Emma to start blocking.

It was obvious at the first subtle signs of puberty. Ms Basques said it was time to start. She asked that their full names be used because they consider themselves advocates of the treatment.

For a long time, patients over the age of 18 were the only ones allowed to receive medical treatment for their gender identity. In the 90s, a hospital clinic in Amsterdam started treating adolescents.

By the time Emma began taking blockers, in 2019, multiple medical groups had endorsed their use for gender dysphoria.Credit...Verónica G. Cárdenas for The New York Times

Puberty blockers can be injected or placed in the body. The best-known is Lupron. The F.D.A. approved them for use in the United States and elsewhere to treat a number of diseases. The Dutch doctors believed that if blockers were safe for patients with central precocious puberty, they would also be safe for trans adolescents.

The first trans patient to be treated with blockers was 13 years old. He looked more masculine as a result of Halting female puberty. The medical team found that the patients' mental health and well-being improved after they were prescribed blockers and hormones.

They were usually miserable when they came in and felt like an outsider. You see them blossom after a few years after you have done this treatment.

She worked with a small international group in 1998 to include puberty blockers and hormones for adolescents in the treatment guidelines for trans people.

She admitted that the Dutch doctors hadn't published any research findings. The one who oversaw trans medical treatment in England was cautious.

The doctors in the group were reassured by the initial results from Amsterdam. Many trans adolescents experience psychological distress.

“It was just really exciting,” Emma said of starting her transition. “I finally got to be who I was.”Credit...Verónica G. Cárdenas for The New York Times

The doctors debated if puberty blockers would hurt the children.

The Dutch said that the drugs were not causing a problem.

She hoped that physicians in other countries would adopt the Dutch protocol to document and share their results. Only patients who had presented as trans since early childhood were treated by her clinic. They had to be 12 for puberty blockers and 16 for hormones.

Similar criteria were advised by the international standards of care Recommendations were not requirements. The use of puberty blockers is going to spread soon. The United States and Canada do not have a centralized health system. The first American clinic for the treatment opened in Boston Children's Hospital in 2007.

Some children were started on blockers at the first sign of puberty, while others were prescribed hormones. Doctors believed that earlier treatment would lead to more successful medical transitions, and wanted to spare patients the difficulty of watching their peers develop.

If the doctor in Arizona prescribed blockers and didn't start hormones for five years, the patients would be 12 years old.

Dr. Peggy Cohen-Kettenis was a psychologist in the Dutch clinic that pioneered treatments for transgender youths. “They were usually coming in very miserable,” she recalled. With treatment, she said, “you see them blossoming.”Credit...Marlena Waldthausen for The New York Times

Activists for the gay, lesbian, bisexual and transexual community wanted easy access to the treatment. Dr. Spack spoke at the Philadelphia medical convention about how he started to treat adolescents with blockers. Like many of her generation, Ms. Burleton was unable to medically transition until adulthood. She said that treating adolescents with blockers was a game-changing thing.

Ms. Burleton wanted the practice to be adopted by the doctors. She said that they could prevent them from being emotionally broken.

In order to allow for Medicaid coverage of puberty blockers for adolescents identifying as trans, advocates succeeded. They helped get approval in Oregon for a variety of medical workers to administer blockers if overseen by an endocrinologist.

The Dutch psychologist, Dr. Cohen-Kettenis, said that the treatment was given by people who were not knowledgeable. There was a big worry.

Multiple medical groups endorsed the use of blockers for gender dysphoria by Emma Basques. The limited research on the effects of the drugs on trans youth was described as low quality by the American Academy of Pediatrics. The organizations were encouraged by the treatment.

It is not uncommon for research to lag behind the launch of new treatments and for drugs to be used off-label on patients without F.D.A. approval.

Jenn Burleton, an advocate from Oregon, speaking at a support group for parents whose children identify as transgender.Credit...Verónica G. Cárdenas for The New York Times

According to an F.D.A. spokeswoman, doctors have the ability to do so, but also noted that just because a drug has been approved for one class of patients doesn't mean it's safe for another.

There isn't a centralized way to track blocker prescriptions in the US. There was a sharp increase in the number of children diagnosed with gender dysphoria over the course of a year. The data shows that 4,780 patients with that diagnosis were put on puberty blockers. The data doesn't capture many cases in which insurance doesn't cover the drugs for that use, leaving families out of pocket.

The makers of another blocker were asked to seek F.D.A. approval for their use among trans adolescents. Drugmakers would have to fund research for a small group of patients. The physicians argued that regulatory approval could help establish the safety of the treatment and expand insurance coverage, which can cost tens of thousands of dollars a year. The decision was made by both companies.

For two years, Emma Basques was on blocker. After she turned 13 in October of last year, a doctor in the Portland, Ore. suburb where her family had moved started her transition by giving her hormones. As her classmates grew older, it became more awkward to be left behind. She thought she was ready.

Emma thought it was exciting. It was time for me to be who I was.

A skeleton model at the Baylor College of Medicine in Houston. A full accounting of blockers’ risk to bones is not possible. Because most treatment is provided outside of research studies, there’s little public documentation of outcomes.Credit...Callaghan O'Hare for The New York Times

The 11-year-old in New York, who had begun puberty and started at a new school, refused to bathe or go to class for the first time, expressing a desire to no longer have a girl's body

The parents wanted the drug to bring emotional stability and time to think about the next step.

The mother said that if everyone thinks this will help, then we need to give it a try.

In the first two years, the patient was taking Prozac and the blockers. At the beginning of the third year, there was a bone Scan. The teen's bone density plummeted as much as 15 percent in some bones, a condition of weakened bones more common in older adults.

The doctor said testosterone would help the teen regain strength in his bones. The parents didn't trust the medical counsel.

The mother said that she was angry. I'm worried we've done permanent damage.

A Texas teenager had very low bone density in the lumbar spine after a year on blockers, records show. No baseline bone scan had been performed at the outset of treatment.Credit...The New York Times

It is not possible to account for the risk of bones. While the Endocrine Society recommends baseline bone scans and then repeat scans every one to two years for trans youths, there is little guidance about whether to do so. Some doctors recommend regular scans and calcium, while others don't. Most treatment is provided outside of research studies.

The drugs are linked to deficits in bone development. During the teen years, bone density tends to go up. The analysis looked at seven studies from the Netherlands, Canada and England. While on blockers, the teens did not gain any bone density, on average, and lost significant ground compared to their peers, according to an analysis by a researcher.

The findings are in line with what practitioners have seen. The drugs have an effect on bone density, which is why they get behind.

Many doctors are reassured by the rebound seen in the children who take blockers for early puberty. Their bone strength can be fully recovered after they stop using drugs at about 11 years old, which can last up to five years. Patients who identify as trans take the drugs later in life, disrupting puberty and limiting the development of their bodies.

Dr. Gordon said that was the difference. The window of puberty is shortened.

The bone development of trans patients can be tracked in two small studies. Dozens of patients started blocking at 14 or 15 in both studies. The participants saw their bones strengthen on average once on hormones after following one study through age 18 and the other through age 22. Trans men were close to average levels but trans women were far below.

Dr. Catherine Gordon, a pediatric endocrinologist and bone researcher at Baylor, is leading a study on the effects of puberty blockers on bone development in transgender youths.Credit...Callaghan O'Hare for The New York Times

There is a false sense of security, according to the doctor.

Doctors don't think the effects on bones are a reason to stop using drugs in adolescents. They think the risks should be taken into account when making patient decisions.

If harm resulted from the use of blockers, it wouldn't be apparent until decades later with broken bones. The dangers could be more immediate for children who already have weak bones. There isn't a systematic record-keeping of such cases.

After more than a year on blockers, a 15-year-old in Texas, who had not had a baseline scans, showed spine bone density so low that it was below the first percentile for the teen's age and weight.

Emma takes calcium, makes an effort to exercise and has undergone scans showing that her bones are healthy.Credit...Verónica G. Cárdenas for The New York Times

An X-ray showed osteoporosis and a compression fracture in the spine of a boy who took drugs from age 11 to 14 with no bone scans until the final year of treatment.

The blockers have caused a patient to suffer from continued back pain.

Some practitioners in the United States and Australia don't give drugs to patients who are well into puberty because of the risk to bones.

Stephen Rosenthal is the medical director of the University of California, San Francisco.

blockers will not be prescribed as a stand alone treatment for anyone over 14. There are more and more youths who don't want to grow up into either male or female bodies. He made it clear that nobody stays on a blocker.

Dr. Rosenthal is one of the principal investigators in the N.I.H. study. He said that their research was delayed because of the Pandemic. The papers on the effects of blockers on bones should be published next year.

The benefits of using blockers to alleviate gender dysphoria are more important than the risks of bones, according to Dr. Rosenthal. He was one of the doctors who filed statements in the case.

Emma Basques has undergone scans that show her bones are healthy and she takes calcium. Her mother said she couldn't imagine how life would be for Emma if she hadn't been given blockers.

Emma said she wouldn't like her body.

The parents in New York decided to end treatment for their teen because he hasn't had a follow-up Scan to see if he has improved.

The mother doesn't think we have the science to prescribe these drugs.

“I wish I hadn’t been steered into transitioning the way I was, and that I had been told there were other ways to cope with the discomfort of puberty,” Ms. Chavira said.Credit...Verónica G. Cárdenas for The New York Times

Jacy Chavira cut her hair short and began binding her chest when she was 13 years old. Jacy's parents and a therapist agreed that gender dysphoria, a condition Jacy learned about from a magazine, could explain the mounting anxiety and discomfort she was experiencing.

She became fixated on moving ahead with a medical transition after being on blockers. She was happy when her doctor prescribed testosterone. She began to have doubts. She was putting on dresses even though she was growing more masculine. She was concerned about the loss of feeling in the nipples during her breast removal consultation at 17 years old. She didn't want to go through with the surgery.

She realized that she would be making a mistake if she continued with a gender transition. She said that she believed it was an issue with her identity and not just the physical female part of it.

In British and Dutch studies, 98% of patients who take puberty blockers move on to hormones. Many doctors see the evidence that the right adolescents are getting the drugs as proof that they are getting the drugs.

The number of medical providers has gone up over the past decade. In some cases, blockers can be prescribed at the first signs of puberty as early as 16 years old. During puberty and throughout adolescence, blockers can be provided, according to the American Academy of Pediatrics.

Doctors and researchers are concerned about puberty blockers disrupting a formative period of mental growth. Significant leaps in brain development can be seen with adolescence. Sex hormones are linked to social and problem-solving skills. It is thought that brain growth is related to gender identity.

Jacy at age 14, while on blockers. “I believe it was an issue with my identity,” she said, “accepting who I was, and not just the physical female portion of it.”Credit...Verónica G. Cárdenas for The New York Times

31 psychologists, neuroscientists and hormone experts called for more study of the effects of blockers on the brain in a 2020 paper.

One of the authors of the paper said, "If the brain is expecting those hormones at a certain time and doesn't, what happens?" "We don't know"

The minimum age for starting blockers and hormones has been lowered in the Amsterdam clinic. They are very careful in choosing patients.

When is gender identity fixed or not is always a concern for us. When do you fully understand the consequences of such treatment? asked Dr. Annelou de Vries.

There are a lot of uncertainties about the effects of blockers for some medical professionals.

There are seven doctors in Florida who recently wrote to the state health department requesting that the use of treatments for adolescents be limited to research settings.

It is difficult to make a conclusion that we are doing the right thing without a lot of data. At a state hearing in July, he voiced his concerns about whether or not to allow Medicaid coverage for medical treatment for people with a gender identity problem.

Ms. Chavira halted her medical treatment at 18, but she is left with a voice that sounds like a man’s and other enduring physical changes.Credit...Verónica G. Cárdenas for The New York Times

Emma and her parents acknowledge that it can be hard to fully grasp all the possibilities of treatment. Infertility is one of the effects of starting blockers at the first stage of puberty. Emma was told that she would need to stop treatment at some point in the future in order to preserve fertility.

Emma had a clear idea of what she wanted during her medical transition. All this other stuff was not clear. Her father said they worked hard to make sure she understood some of the more complicated things.

When Dutch doctors began to use blockers and hormones on trans youth decades ago, they warned of the possibility of false positives.

Many practitioners think the total numbers are small because there is no official tracking. Scores of accounts have appeared in social media and news stories.

Five years after starting to transition, she was no longer identified as a trans person. She had been treated at the clinic. A judge ruled that patients under the age of 16 couldn't consent to puberty blocking drugs.

Jacy Chavira believes that drugs were prescribed too quickly. She stopped her medical treatments at 18. She has a voice that sounds similar to a man's.

She wished the doctors had asked more questions. I wish I hadn't been steered into transitioning the way I was and that I had been told there were other ways to deal with puberty.

Sweden is working to standardize adolescent trans medical treatment and restrict it to research settings because of the uncertain number of cases like Jacy's and the rising number of patients with gender Dysphoria.

Dr. Riittakerttu Kaltiala is the chief of adolescent Psychiatry at a gender clinic in Tampere. As the Florida medical board considered banning treatment, Dr. Kaltiala testified.

In the United States, the public discourse about trans care is getting more inflammatory.

The American Academy of Pediatrics and other medical groups urged the Justice Department to investigate threats against physicians and hospitals that provide trans medical treatment to adolescents. As more Republicans frame the treatment as child abuse, some doctors are afraid to discuss their work.

Several of the doctors who spoke to The Times did not want to be named, and more than a dozen refused to be interviewed.

The climate could have a chilling effect on research according to Dr. Natalie Nokoff, who recently conducted a study showing that a longer treatment period on puberty blockers was associated with a lower bone density

Concerns are being raised that people's research could be misconstrued and used for political gain.

The families of Emma Basques, Ms. Chavira and the teen in New York are sad about the possibility of such an outcome. They both share the same hopes for the future of trans medicine.

There is a methodology.

There is an association between puberty blockers and bone density in about 500 adolescents.

DEXA scans were used to measure bone density at the spine and hip. Group means were looked at because not every study had individual person data. The findings were weighted according to the number of people in the study.

There was no change in bone density when adolescents were on blockers. The adolescents' Z- scores, a measure of bone density that is benchmarked to peers, fell during treatment with blockers.

There are studies included.

There is bone mass in young adulthood after Gonadotropin-Releasing Hormone Analog Treatment and Cross-Sex Hormone Treatment.

The effect of puberty suppression and cross-sex hormone therapy on bone turnover in adolescents is studied.

The effect of GnRH Analogue Treatment on Bone Mineral Density in Young Adolescents with Gender Dysphoria was found in a large national cohort.

Testosterone treatment in adolescents with gender Dysphoria can cause physical changes.

GnRH analogues and subsequent gender-Affirming Hormones can be used to treat bone development in adolescents.

The short-term outcomes of puberty suppression in a group of young people with persistent gender Dysphoria in the UK.

A study on puberty suppression, bone mass and body composition in young people with gender dysphoria.