WASHINGTON — The Obama administration struck a major blow for transgender rights by quietly ending a decades-long blanket ban that prevented Medicare from covering sex reassignment surgery.

The Department of Health and Human Services' Departmental Appeals Board, an internal review structure within the byzantine federal agency, issued a ruling that ended a ban on Medicare even considering covering sex reassignment surgery and related care because a fear of "serious complications" resulting from the "experimental" surgery. That language was issued in 1981, and most medical professional organizations now consider sex reassignment surgery a safe and accepted procedure. The DAB ruling noted the change in how sex reassignment surgery is understood 33 years after the Medicare ban was issued.

"Even assuming the [National Coverage Determination]'s exclusion of coverage at the time the NCO was adopted was reasonable, that coverage exclusion is no longer reasonable," reads the ruling. "This record includes expert medical testimony and studies published in the years after publication of the NCO."

"Denying Medicare coverage of all transsexual surgery as a treatment for transsexualism is not valid under the "reasonableness standard" the Board applies," the HHS board ruling continues.

Experts say the change to Medicare could have far-reaching implications for American medicine, helping to drive more private insurers to offer coverage for sex reassignment surgery and related care. Though it fits within President Obama's promise to make the government fairer to LGBT Americans, the DAB announcement was a relatively quiet one. The White House did not trumpet the move, and advocates for the change issued a joint statement hailing it but downplaying it as a revolutionary change for transgender people, instead casting it as bringing Medicare up to speed with the rest of the medical profession.

"This decision removes a threshold barrier to coverage for medical care for transgender people under Medicare," leaders of the ACLU, Gay & Lesbian Advocates & Defenders and the National Center for Lesbian Rights — the groups that fought for the change — said. "It is consistent with the consensus of the medical and scientific community that access to gender transition-related care is medically necessary for many people with gender dysphoria."

Advocates for the change have noted that the change won't automatically mean Medicare will start covering sex reassignment surgery and related care, but will no longer be prevented from doing so when claims are made.

The statement was a rare on-record communication from a tight-lipped coalition that has sought to avoid controversy by keeping the DAB deliberations out of the headlines. When the Obama administration first broached the idea of allowing Medicare to cover transgender surgery through a public process in 2013, conservative critics launched a vocal opposition campaign that caused the administration to step back and pursue the change through the less public DAB.

As if making the administration's point, the advocates noted that the shift didn't mean that Medicare will immediately be footing the bill for sex reassignment surgery.

"The removal of the exclusion of coverage for surgical care for Medicare recipients means that individuals will not automatically have claims of coverage for gender transition-related surgeries denied," reads the statement from the advocates. "They should either get coverage or, at a minimum, receive an individualized review of the medical need for the specific procedure they seek, just like anyone seeking coverage for any other medical treatment."