OKLAHOMA CITY (AP) — A federal judge in Tulsa declined to stop a new law from taking effect that makes it a felony crime for health care workers in Oklahoma to provide gender-affirming medical care to young transgender people.

U.S. District Court Judge John Heil III issued his order late Thursday denying a motion for a preliminary injunction sought by the plaintiffs, who include a medical provider and family members of transgender children in Oklahoma. Heil wrote that the plaintiffs had not demonstrated that parents have a fundamental right to choose such medical care for their children.

“This an area in which medical and policy debate is unfolding and the Oklahoma Legislature can rationally take the side of caution before permitting irreversible medical treatments of its children,” Heil wrote.

The new law, which bans medical treatments like puberty-blocking drugs or hormones for those younger than 18, was passed by Oklahoma’s Republican-controlled Legislature and signed by Gov. Kevin Stitt in May. Enforcement had been on hold under an agreement between the plaintiffs and Oklahoma Attorney General Gentner Drummond, whose office is defending the law.

“The attorney general’s office continues to fulfill its duty to defend Senate Bill 613 and has won a ruling that results in full enforcement of that law,” Drummond spokesman Phil Bacharach said in a statement.

Oklahoma’s law includes a six-month transition period for minors who were already receiving puberty-blocking drugs or cross-sex hormones. That period ends early next month.

Attorneys for the plaintiffs, including the American Civil Liberties Union, the ACLU of Oklahoma, Lambda Legal and the law firm Jenner & Block LLP, issued a joint statement vowing an appeal and decrying the judge’s decision as a “devastating result for transgender youth and their families.”

“Denying transgender youth equality before the law and needlessly withholding the necessary medical care their families and their doctors know is right for them has caused and will continue to cause serious harm,” they said.

At least 22 states have enacted laws restricting or banning gender-affirming medical care for transgender minors, and most of those states face lawsuits similar to the one in Oklahoma.

A federal judge in June declared that Arkansas’ ban was unconstitutional, the first ruling to overturn such a prohibition. Arkansas was the first state to enact a ban on gender-affirming medical care for minors.

The 8th U.S. Circuit Court of Appeals on Friday granted Arkansas’ request that the full court, rather than a three-judge panel, hear its appeal of the judge’s ruling.