By GEOFF MULVIHILL, Associated Press

The U.S. Supreme Court has upheld Tennessee’s ban on gender-affirming surgery for transgender youth in a ruling that’s likely to reverberate across the country.

Most Republican-controlled states already have similar bans.

In his majority opinion Wednesday, Chief Justice John Roberts wrote that Tennessee’s ban does not violate the Constitution’s equal protection clause, which requires the government to treat similarly situated people the same.

Since President Donald Trump returned to office this year, the federal government has been trying to restrict access.

Here are some things to know about gender-affirming care and the court’s ruling:

What is gender-affirming care?

Gender-affirming care includes a range of medical and mental health services to support a person’s gender identity, or their sense of feeling male, female, neither or some combination of both. Sometimes that’s different from the sex they were assigned at birth.

The services are offered to treat gender dysphoria, the unease a person may have because their assigned gender and gender identity don’t match. Studies, including one from 2023 by researchers at institutions including London Children’s Hospital and Children’s Hospital of Philadelphia, have found the condition is linked to depression and suicidal thoughts.

Gender-affirming care encompasses counseling and treatment with medications that block puberty and hormone therapy to produce physical changes. Hormone therapy for transgender men causes periods to stop, increases facial and body hair and deepens voices. The hormones used by transgender women can have effects such as slowing growth of body and facial hair and increasing breast growth. Fewer than 1 in 1,000 U.S. adolescents receive gender-affirming medications, a study released this year found.

Gender-affirming care can also include surgery, including operations to transform genitals and chests. These surgeries are rarely offered to minors.

There are documented uses of genital surgery for adults dating back to the 1920s. But for youth, gender-affirming care has been more common since the 1990s.

What is the controversy?

As a medical consensus emerged in support of gender-affirming care for youth, the issue also became politically divisive in other ways. Some states approved measures to protect transgender people, who make up around 1% of the nation’s population.

Many critics dismiss the idea that gender is changeable and lies along a spectrum. About two-thirds of U.S. adults believe that whether a person is a man or woman is determined by biological characteristics at birth, an Associated Press-NORC Center for Public Affairs Research poll conducted in May found.

In the last five years, most GOP-controlled states have passed laws to block transgender girls from sports competitions for girls. About half the Republican-controlled states have now banned transgender people from using school bathrooms that align with their gender identity.

Opponents of gender-affirming care sometimes refer to it as “mutilation” and say people who transition when they’re young could later regret it.

What could the ruling mean for bans in states besides Tennessee?

In addition to Tennessee, 26 other states have passed bans or restrictions on gender-affirming care for youth. Judges have struck down the bans in Arkansas and Montana, though the legal fights there aren’t over.

All of the laws have been adopted in the past five years and nearly all have been challenged in court.

The Supreme Court’s decision may doom some of those challenges. But lawyers who challenged Tennessee’s law said the ruling applies only to that policy – and that it doesn’t automatically end the cases against other bans on gender-affirming care.

Lambda Legal lawyer Karen Loewy noted that the opinion focused on the fact that it involved minors and that the court did not find sex-based discrimination against transgender people.

Further, some of the lawsuits against the bans — including in Kansas, Montana, North Dakota and Ohio — are based on arguments rooted in state constitutions. It still possible that judges could find more protections in those state constitutions than are in the U.S. Constitution.

What will the ruling mean for states without bans on gender-affirming care?

It probably won’t make any difference immediately.

Several of those states have laws or executive orders intended to protect access to gender-affirming care for transgender minors.

But the question about whether the care will continue isn’t only about what’s legal. It’s also about funding.

That’s where Trump comes in.

Trump campaigned last year pledging to rein in rights of transgender people. He’s followed through on many fronts, though court challenges have resulted in some of his efforts being blocked, at least for now.

What has Trump done on transgender issues?

He has ordered that no federal taxpayer money be used to pay for the care for those under 19. Enforcement of that order is on hold.

Trump has also tried to block federal funding from institutions — including hospitals and the universities that run some of them — that provide gender-affirming care for youth. A judge has blocked that effort while challenges to it proceed.

His administration published recommendations that therapy alone – and not medication – be used to treat transgender youth. The position contradicts guidance from major medical organizations. But it could impact practices.

Other actions Trump has taken including initiating the removal of transgender troops from military service; ordering that transgender women and girls be kept out of sports competitions for females; erasing the word “transgender” from some government websites; and saying the government would recognize people only by their sex at conception.

That’s resulted in efforts to move transgender women inmates to men’s prisons and change how passports are issued to transgender and nonbinary people. A judge this week blocked the Trump administration from limiting passport sex markers for many transgender and nonbinary Americans.

Associated Press writers Matthew Brown in Billings, Montana; Jack Dura in Bismarck, North Dakota; and Kenya Hunter in Atlanta contributed to this report.