WPATH draft guidance on best practices for treating adults and minors with gender dysphoria initially set age minimums to 14 for hormonal treatments, 15 for mastectomies, 16 for breast augmentation or facial surgeries, and 17 for genital surgeries or hysterectomies. But the final guidance published by WPATH entirely removed age-based recommendations.

Documents revealed in June 2024 that staff members for Levine, a biological male who identifies as a transgender woman, asked WPATH to entirely remove age recommendations from its 2021 guidance to counteract conservative criticism of gender transition medicine for minors.

Cassidy, who at the time was the leading Republican on the Senate health committee, sent letters in October 2024 to WPATH, AAP, and the Endocrine Society asking for more information.

Now, Cassidy is extending the investigation as the chairman of the committee by requesting that AAP and the Endocrine Society share all communications with the Biden administration about transgender medical procedures for children. 

In the letters sent Tuesday, Cassidy described gender transition treatments and surgeries as “irreversible, with damaging, long-lasting side-effects that affect a child or adolescent’s immediate physical, mental, and emotional development and their future wellbeing as an adult.”

“Americans have every right to know the scientific rigor supporting guidelines issued by your organization, particularly given that these guidelines are widely used and relied upon by physicians and healthcare providers, and patients, including minors,” Cassidy wrote to both organizations. 

Neither AAP nor the Endocrine Society has walked back its support for gender transition medicine for minors, even as the American Medical Association and the American Society of Plastic Surgeons have supported age restrictions on gender-related surgical procedures for minors.

Transgender medical procedures and treatments for children have been a focal point for Republicans, with some data suggesting that the issue was a key factor in President Donald Trump’s 2024 election.

Trump signed an executive order on the first day of his second term last year, making biological sexes male and female the official respective definitions of man and woman. A week later, he signed an additional executive order directing his agencies to find ways to curtail transgender procedures for children, calling them “sex-rejecting” as opposed to “gender-affirming.” 

In December, the Department of Health and Human Services moved to prohibit Medicare funding for all hospitals and healthcare systems that provide transgender medical services for minors, effectively instituting a nationwide ban, as nearly all healthcare providers accept Medicare.

A Biden-appointed judge in Oregon last week overturned HHS’s funding ban, siding with 21 Democrat-led states that sued the Trump administration for overstepping its authority to regulate medical policy decisions, which are usually made at the state level. 

Cassidy, in his Tuesday letter, praised Trump and his health officials for “taking decisive action” to protect minors from “the reckless decisions of medical organizations and interest groups that claim to act based on ‘science’ and in the best interests of children.” 

But despite Cassidy’s support on this and several other issues, Trump did not endorse him for reelection this fall, largely because Cassidy voted to impeach the president during his first term in 2021. Instead, Trump and Louisiana Gov. Jeff Landry endorsed Rep. Julia Letlow (R-LA) for the May 16 primary.

As of a March 3 poll from the fiscally conservative state think tank Pelican Institute, Cassidy is leading the pack, with 30% of those surveyed supporting the sitting senator. Only 15% said they supported Letlow, and 17% supported State Treasurer John Fleming. A quarter of voters, 24%, said they were undecided.

Four in 10 voters said the cost of living was their No. 1 concern heading into the primary. Only 11% listed healthcare as their top priority.