By Brendan Pierson

A federal appeals court on Thursday allowed Tennessee and Kentucky to enforce laws banning gender-affirming medical care for minors, such as puberty blockers, hormones and surgery.

By a 2-1 vote, the Cincinnati, Ohio-based 6th U.S. Circuit Court of Appeals rejected a challenge by families of transgender children who had argued that the bans discriminated on the basis of sex.

The ruling is the second by a federal appeals court upholding such laws, after the 11th Circuit ruling revived an Alabama law. On the other side of the ledger, federal district courts in Arkansas, Florida, Georgia and Indiana have overturned such bans, as has a state court in Montana.

Mainstream U.S. medical associations say gender-affirming care is appropriate and potentially life-saving treatment for gender dysphoria, or distress caused by the mismatch between transgender people's sex assigned at birth and their gender identity.

But the 6th Circuit panel sided with proponents of gender-affirming care bans who say the treatments are unproven and risk permanently harming children.

"This is a relatively new diagnosis with ever-shifting approaches to care over the last decade or two. Under these circumstances, it is difficult for anyone to be sure about predicting the long-term consequences of abandoning age limits of any sort for these treatments," wrote Chief Judge Jeffrey Sutton, who was joined by Judge Amul Thapar.

In dissent, Judge Helene White said the Tennessee and Kentucky statutes "cannot pass constitutional muster" and "intrude on the well-established province of parents to make medical decisions for their minor children."

Both the Tennessee and Kentucky bans were blocked by trial court judges, but the 6th Circuit in July allowed Tennessee's ban to take effect while it considered the state's appeal.

The judge overseeing the Kentucky case then allowed that state's ban to take effect as well, saying he was bound to follow the 6th Circuit, which hears appeals from both states.

Lawyers for the families who brought the Tennessee challenge, including Lambda Legal and the American Civil Liberties Union, called the ruling a "devastating result for transgender youth and their families" and said "we are assessing our next steps" in defense of transgender rights.

(Reporting by Brendan Pierson, Mike Scarcella in Washington and Daniel Trotta in Carlsbad, California; Editing by Leslie Adler)