New Study on Puberty Blockers Released Amid Controversy

A long-anticipated study assessing puberty blockers has been published, despite efforts from the physician who led the research to keep it under wraps.

The previous medical director of one of the largest child gender clinics in the U.S. chose not to disclose findings from a government-funded study involving 95 children treated with puberty blockers, primarily out of fear that the results could undermine her professional stance and beliefs.

‘Every taxpayer should be furious that this research was encouraged and funded.’

This study, revealed by the Oversight Project and published on Thursday by the Daily Signal, effectively contradicts the narrative favored by proponents of gender ideology, just as Olson-Kennedy feared.

Details of Suppression

Johanna Olson-Kennedy, the president of the U.S. Professional Association for Transgender Health, has openly shared her strong views.

As the former head of the gender clinic at Children’s Hospital Los Angeles, which dealt with medical interventions for minors, Olson-Kennedy has publicly opposed mandatory psychological evaluations prior to surgical interventions, likening the choice of teen girls to undergo mastectomies with standardized testing. Moreover, she has faced accusations of administering transition hormones to children as young as 12.

Just a year before her clinic closed in July 2025 due to government scrutiny, Olson-Kennedy revealed that her team had withheld the results of a long-term study funded by the National Institutes of Health focusing on the “long-term outcomes of medical treatment for transgender youth.”

When questioned about her refusal to publish data that cost taxpayers at least $9.6 million, Olson-Kennedy suggested that these findings could provoke political backlash that has already led to bans on youth gender treatments in over 20 states, one of which may soon come before the Supreme Court.

Olson-Kennedy stated, “I do not want our work to be weaponized. It has to be exactly on point, clear, and concise. And that takes time.”

The political sensitivity surrounding her findings stemmed from the apparent conclusion that the “gender-affirming care” offered at the clinic was not as beneficial as promoted.

Amy Tishelman, a psychologist at Boston College involved in the study, expressed understanding of the apprehensions regarding the misuse of data but emphasized the importance of sharing scientific findings with the public.

Tishelman also noted that the study showed no psychological improvements in the youth treated with puberty blockers—drugs sometimes used to chemically castrate sex offenders—but suggested that a lack of change does not necessarily indicate negative outcomes.

Findings of the Study

The recently published report from Olson-Kennedy’s study, titled “The Impact of Early Medical Treatment in Transgender Youth,” indicates that two years of treatment with puberty blockers did not significantly affect the mental health of participants. Among those studied, about a quarter had suicidal thoughts, and 8% had previously attempted suicide.

Despite advocacy from various experts claiming that puberty blockers are a “lifesaving option” and arguing against withholding treatment for gender dysphoria—which they believe could lead to serious health consequences—the study suggests otherwise.

While it was claimed that puberty blockers would enhance mental well-being, the study concluded:

“After two years of medical intervention starting with blockers, mental health remained relatively stable and was comparable to the general population. These youth showed no worsening of their mental or emotional health, and incidents of suicidality decreased over 24 months. Mental health scores were stable within a clinically non-significant range.”

In an earlier report to the National Institutes of Health, Olson-Kennedy had speculated that children on puberty blockers for two years would show “reduced symptoms of depression, anxiety, trauma, and self-injury, as well as enhanced body esteem and life quality,” according to the Times.

Neal Cornett, the director of state litigation for the Oversight Project, remarked that the study’s conclusions affirm what many might expect—that treating troubled youth with puberty blockers and hormones doesn’t actually improve their mental health. He criticized the research’s funding, expressing indignation that taxpayers financed a decade of unrestrained clinical practices.

Cornett further mentioned that Olson-Kennedy likely feared that the report would jeopardize the rationale supporting her research, indicating genuine scrutiny of a widely contested practice.

While the implications of Olson-Kennedy’s study have significant repercussions for gender activists, several substantial studies from both the U.S. and the U.K. have indicated that the risks associated with puberty blockers might outweigh any potential benefits.

The Cass Review, commissioned by NHS England, highlighted that:

• The reliability of earlier studies suggesting benefits from puberty blockers was deemed “poor”;
• A high-quality review by the University of York found no evidence supporting improvements in body image or gender dysphoria;
• There is evidence that puberty blockers may worsen psychological functioning;
• Most children’s gender dysphoria seems to resolve naturally by the onset of puberty;
• There may be temporary or permanent disruptions to brain maturation caused by these blockers.

The extensive peer-reviewed report from the Department of Health and Human Services in 2025 also listed numerous physical risks associated with puberty blockers, such as decreased bone mineral density, impaired skeletal development, infertility, and sexual dysfunction.

As of now, Olson-Kennedy has not publicly commented on the situation.