Colorado would ban gender-related surgeries for youth

Voters this November will decide whether to make Colorado the latest state to ban certain gender-related surgeries for people under the age of 18.

Proposition 135 would prohibit doctors from performing surgeries on minors to alter their sex characteristics. It would also ban state or federal funds, Medicaid or private insurance coverage from paying for such surgeries.

Though the debate around the measure has focused on care for transgender kids, the text of the proposition applies broadly and could also impact surgeries for non-transgender youth.

Here’s more information on what the measure would do, how often these surgeries are performed and what both sides say about it.

What would Proposition 135 do?

The measure would prohibit healthcare professionals and others from knowingly performing, prescribing, administering or providing “any surgery to a minor for the purpose of altering biological sex characteristics.”

The measure defines “altering biological sex characteristics” as “treatment in response to a minor’s perception of sex or gender.”

Much of the debate surrounding the measure has been about gender transition surgeries for youth who are transgender. But the text of the proposition doesn’t limit the prohibition to transition surgeries.

The state’s nonpartisan voter guide notes that the measure could also impact surgeries for cisgender, or non-transgender, kids “if the treatment is interpreted as being in response to the minor’s sex or gender perception.”

The measure contains exemptions for male circumcision, as well as for people born with “a medically verifiable disorder of sex development.” There is also an exemption for “acquired physical or chemical abnormalities.”

The measure does not provide a list of these disorders or abnormalities or any further definition, so it would be up to medical providers’ and state regulators’ interpretations as to what qualifies.

Proposition 135 does not ban non-surgical forms of gender-affirming care, such as hormone therapy or puberty-blocking drugs. It also does not ban gender-related counseling services or other support for social transitioning. 

The measure needs a simple majority vote to pass. It changes state statutes — not the constitution — so lawmakers could potentially make amendments to it, or undo it altogether, later if it were to pass. 

How often do these surgeries occur now?

The measure does not provide a list of the types of surgeries that would be prohibited. 

The nonpartisan voter guide, which is prepared using input from groups and people on both sides of the issue, provides examples of surgeries that could be banned. That list includes altering, removing or restructuring sexual and reproductive organs; changing body shape or facial appearance; or altering vocal characteristics.

Available data and research suggests these surgeries are rare for transgender youth in Colorado and nationwide. Some of the surgeries may be more common for cisgender youth.

A 2024 study by researchers at the Harvard T.H. Chan School of Public Health looked at national insurance claims data for young people with and without a transgender-related diagnosis. The study found that, for 2019, the number of transgender teens ages 15 through 17 who had a gender-affirming surgery was 2.1 for every 100,000 total teens in the age group. The rate was 0.1 for teens ages 13 through 14, and the study found no gender-affirming surgeries for trans youth 12 and younger.

Medicaid data provided to The Colorado Sun by the state Department of Health Care Policy and Financing also suggest the surgeries are rare.

The dataset does not break down claims specifically for surgeries, but it lumps claims for gender-affirming care for trans patients into three categories: hormones, which encompasses prescriptions; procedures, which involves care provided at a doctor’s office; and inpatient, which involves care provided at hospitals. The latter two categories could potentially include some types of surgeries.

In total, Medicaid spent about $145,000 on procedures and $1.3 million on inpatient care from the 2019-2020 fiscal year through the 2024-2025 fiscal year. The number of patients who received such care in any given year was too small for the state to release due to privacy rules.

The Harvard study found that gender-related surgeries may be more common for non-transgender youth. For example, the study looked at the total number of breast-reduction surgeries performed on transgender minors and cisgender boys in 2019 and found that 97% were performed on cisgender boys, who may receive the treatment due to a condition called gynecomastia.

Proposition 135’s proponents say the number of surgeries for youth identifying as transgender may be higher than what shows up in insurance data due to accusations of improper billing. Hospitals have denied improper billing.

Proponents also cite data published by the organization Do No Harm, which has ties to conservative causes, that claim roughly two dozen hospitals or clinics in Colorado provided gender-affirming surgeries to 60 minor patients from 2019 through 2023. Included on that list are Children’s Hospital Colorado, Denver Health and UCHealth.

Hospitals nationwide have questioned the database’s accuracy. Children’s and UCHealth say they have never performed gender-affirming surgeries on transgender minors. Denver Health says it stopped surgeries in early 2025. 

How many states have banned gender-affirming surgeries?

As of late September, 27 states have enacted laws banning or restricting gender-related surgeries for transgender youth, according to the nonpartisan health policy research organization KFF.

In two of those states, Kansas and Montana, the laws have been blocked at least temporarily due to legal challenges.

According to KFF, 50% of trans youth ages 13 through 17 nationwide live in a state with a restriction on gender-affirming care.

What do major medical associations say about gender-affirming surgery?

There is not a profession-wide consensus on the best way to handle gender-affirming surgeries for youth who identify as transgender.

In February, the American Society of Plastic Surgeons issued a position statement recommending “that surgeons delay gender-related breast/chest, genital, and facial surgery until a patient is at least 19 years old.” The statement cited a lack of clarity from available research about the benefits and harms of such surgeries and said “the natural course of pediatric gender dysphoria remains poorly understood.” However, the statement was careful to note that it “is not a clinical practice guideline.”

Shortly after that, the American Medical Association told reporters that it agrees with the ASPS’s recommendation, though it later noted that AMA policy on gender-affirming care is unchanged. That policy expresses support for evidence-based gender-affirming care, including surgery.

The American Academy of Pediatrics does not appear to have stated a specific policy on gender-affirming surgery. But the organization has voiced support for gender-affirming care broadly, and its president has called federal efforts to restrict it “a baseless intrusion into the patient-physician relationship.”

A separate organization, the American College of Pediatricians, opposes all forms of gender-affirming care, including surgeries. The organization was established in 2002 as a socially conservative alternative to the AAP.

The World Professional Association for Transgender Health, or WPATH, supports gender-affirming surgeries, including for adolescents, but only as part of a comprehensive system of care that includes mental health support and careful consideration. This includes a long prior history of gender-affirming care and an assessment that the young patient “demonstrates the emotional and cognitive maturity required to provide informed consent” and has been fully informed of all risks and consequences.

Who is behind Prop 135 and what do they say?

Proposition 135 is backed by Protect Kids Colorado, an organization made up of parents, grandparents and other citizens who collected signatures across the state to get the measure on the ballot.

The organization is also behind two other measures on the ballot this year: Proposition 134, which concerns participation by transgender people in sports, and Proposition 133, which increases penalties for child trafficking.

The group had raised $152,730 for all three initiatives through mid September, according to state campaign finance records. Its largest donors include Pikes Peak Citizens for Life — a Colorado Springs-based group opposed to abortion — as well as groups tied to conservative Woodland Park evangelist Andrew Wommack and a 501(c)(4) nonprofit tied to Protect Kids Colorado.

As with Proposition 134, the most visible proponent behind Proposition 135 is Erin Lee, a mother in Wellington who says she became concerned about gender-related issues after her daughter joined a gender and sexuality awareness art club at her school, which led her to identify as transgender for about a year before changing her mind.

In an interview, Lee said she became concerned after meeting other families and people known as “detransitioners” — individuals who once identified as transgender and received medical therapy or surgery and later regretted their decision. Echoing language used by President Donald Trump’s administration, Lee called the procedures “sex-rejecting surgeries.”

Lee said she is concerned that children could be making permanent changes to their bodies without understanding the consequences or fully consenting.

“When you talk to these young people and you experience their pain, you think, why not? Why not let them just grow up a little bit?,” she said. “Why not just let them turn 18 before they make these permanent decisions?”

Who is against Prop 135 and what do they say?

Again similar to Proposition 134, a collection of LGBTQ advocacy groups and antidiscrimination organizations are fighting Proposition 135.

These include committees called Families Not Politics, The People’s No and Vote Common Sense. The groups have collectively raised more than $1.7 million, with major contributions coming from the LGBTQ rights group One Colorado, the American Civil Liberties Union and the reproductive rights organizations Cobalt and Planned Parenthood.

Opponents of the measure say that Colorado law already requires parental consent for surgical procedures, that gender-affirming care is done in a careful and evidence-based manner, and that regret among patients is extremely low.

Chris Cook, who lives in Thornton and is the father of an 11-year-old transgender girl, said at a rally against the measure in September that Proposition 135 “would take personal healthcare decisions away from families and trusted medical professionals and hand them to politicians.”

“It would tell parents like me that the government knows better than we do, even when we are working carefully and thoughtfully with providers who know and understand our children,” Cook said.

Would Prop 135 save or cost the state money?

According to Colorado’s nonpartisan voter guide, if the measure passes it may slightly decrease state spending due to no longer paying for the surgeries but it may slightly increase state spending due to enforcement costs. In both cases, the guide uses the word “minimal” to describe the fiscal impact.

How Proposition 135 appears on the ballot

Read the nonpartisan state ballot guide analysis of the measure.

Colorado Sun reporters Jennifer Brown and Jesse Paul contributed to this report.

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