Puberty blockers and gender-affirming hormones are rarely prescribed to U.S. transgender and gender diverse (TGD) adolescents, according to a new study from researchers at Harvard T.H. Chan School of Public Health, Harvard Pilgrim Health Care Institute, and FOLX Health.

The study was published Monday in JAMA Pediatrics.

“The politicization of gender-affirming care for transgender youth has been driven by a narrative that millions of children are using hormones and that this type of care is too freely given. Our findings reveal that is not the case,” said lead author Landon Hughes, Yerby Fellow in Harvard Chan School’s Department of Epidemiology and postdoctoral fellow at Harvard Chan School and Harvard Pilgrim Health Care Institute’s LGBTQ Health Center of Excellence.

A 2024 study led by researchers at Harvard Chan School and Harvard Pilgrim Health Care Institute documented the rarity of gender-affirming surgeries among adolescents. But little is known about hormone use among transgender and gender-diverse adolescents. The researchers analyzed private insurance claims data from 2018 to 2022, representing more than 5.1 million young patients ages 8 to 17. They identified transgender or gender-diverse patients based on a gender-related diagnosis and then checked if they received puberty blockers or gender-affirming hormones. They then calculated the rate of adolescents who are TGD and receiving this care per 100,000 privately insured adolescents according to age and sex assigned at birth.

The study found that less than 0.1 percent of minors with private insurance are TGD and received puberty blockers or gender-affirming hormone treatment. No TGD patients under age 12 were prescribed gender-affirming hormones. Use of puberty blockers and gender-affirming hormones was more common among TGD adolescents assigned female sex at birth than those assigned male sex at birth.

The researchers noted that higher rates of puberty blocker and hormone prescriptions for TGD patients assigned female sex at birth aligned with an earlier onset of puberty for people who are female vs. male sex assigned at birth.

“Our study found that, overall, very few TGD youth access gender-affirming care, which was surprisingly low given that over 3 percent of high school youth identify as transgender,” said senior author Jae Corman, head of analytics and research at FOLX Health. “Among those that do, the timing of care aligns with the standards outlined by the World Professional Association for Transgender Health, the Endocrine Society, and the American Academy of Pediatrics.”

The researchers also noted that the study likely reflects the highest rates of puberty blocker and hormone use by adolescents, given the study used private insurance data, likely reflecting greater access to gender-affirming care. Lower rates would be expected among the uninsured, Medicaid recipients, and those with less comprehensive private insurance.

Isa Berzansky, research analyst at Harvard Pilgrim Health Care Institute, and Brittany Charlton, associate professor in the Department of Epidemiology at Harvard Chan School and founding director of the LGBTQ Health Center of Excellence, were co-authors.