COLUMBIA, Mo. (AP) — A Missouri judge is expected to rule Monday on whether a strict, first-of-its-kind rule in the U.S. on gender-affirming health care can take effect, or if the new rules will remain unenforced as a legal challenge seeking to overthrow them plays out in court.

The rule, which requires documented gender dysphoria for three years and more than a year of therapy, was scheduled to kick in last Thursday.

But transgender Missourians and health care providers sued to block it, claiming Republican Attorney General Andrew Bailey sidestepped the GOP-led Legislature and acted beyond his authority in attempting to regulate gender-affirming health care under the state’s consumer-protection laws.

St. Louis County Circuit Judge Ellen Ribaudo on Wednesday temporarily delayed the rule’s effective date as she considers blocking its enforcement throughout the court battle.

The rule will require people to have experienced an “intense pattern” of documented gender dysphoria for three years and to have received at least 15 hourly sessions with a therapist over at least 18 months before receiving puberty blockers, hormones, surgery or other treatment.

Patients also must first be screened for autism and “social media addiction,” and any psychiatric symptoms from mental health issues would have to be treated and resolved. Some people would be able to maintain their prescriptions while undergoing required assessments.

Bailey has touted the rule as a way to shield minors from what he describes as experimental medical treatments, though puberty blockers and sex hormones have been prescribed for decades and the rule also applies to adults.

Some transgender people have been trying to stockpile their prescribed hormones or find alternative ways to get the medications on their own, out of fear they could lose access to the gender-affirming treatments many credit as life-saving. Some are considering leaving Missouri if the emergency rule isn’t blocked in court.

“This feels like the end of Kansas City being my home,” said Stacy Cay, an autistic transgender woman. “It feels like it’s being taken away.”

Bailey was appointed attorney general by Republican Gov. Mike Parson and took office in January. In a campaign email asking donors for money last week, Bailey said minors are “learning about their genders on TikTok.”

“Think about how frightening that is!” the campaign email said. “And think about how CRAZY it is to expose children to the twisted experiments advocated by extreme transgender activists.”

Interim President and CEO Brandon Hill of Vivent Health, a health care provider with an LGBTQ+ and HIV focus serving Missouri and other states, questioned Bailey’s description of gender-affirming care as “experimental.” Hill said the same hormones are used off-label to treat symptoms of menopause and help some cancer survivors.

“If you’re concerned about the drug and its potential effects, you should be concerned about it for everybody,” Hill said.

He said it is “discriminatory if you decide to isolate one group and decide what their treatment looks like, but not others who use the same exact products.”

Meanwhile, GOP state lawmakers are fighting over competing House and Senate bills to ban all gender-affirming care for minors. The chambers are split over which version they want to send to the desk of Gov. Mike Parson, who is threatening to force the legislature to keep working if nothing is done on the issue by the May 12 end of the session.