The Food and Drug Administration on Monday lifted a decades-old, lifetime ban on blood donation for men who have had sex with other men, replacing it with a 12-month "deferral" period that prohibits such donors from giving blood for a year after their last same-sex contact.

The agency said its updated policy reflects "the most current scientific evidence" and mirrors the approach taken in other countries, such as Australia and the United Kingdom. “We have taken great care to ensure this policy revision is backed by sound science and continues to protect our blood supply," FDA Acting Commissioner Stephen Ostroff said in a statement.

But some gay rights advocates were less than pleased with the 12-month deferral policy, which requires men who have sex with other men to remain abstinent for a year before giving blood. The National Gay Blood Drive, a group that has pushed for rolling back the decades-old ban, said that while it supports FDA’s updated approach, “the revised policy is still discriminatory.”

“While many gay and bisexual men will be eligible to donate their blood and help save lives under this 12-month deferral, countless more will continue to be banned solely on the basis of their sexual orientation and without medical or scientific reasoning,” the group said in a statement. The organization’s founder and director, Ryan James Yezak, said FDA should move toward an approach based on assessing each potential donor’s risk on the basis of individual behaviors.

Daniel Bruner, senior policy director at the Whitman-Walker Health, a D.C. health-care provider that caters to lesbian, gay, bisexual and transgender patients, said in an interview Monday that the deferral period should be no longer than 30 days, given the ability of current testing to detect an HIV infection soon after exposure. He also criticized the new guidelines for continuing a lifetime donation ban on individuals who have engaged in sex work or used non-prescription injection drugs.

"It’s still inherently stigmatizing for gay and bisexual men," Bruner said of the 12-month deferral requirement. "The FDA must do better than this slow chipping away at antiquated bans."

A 2010 study by the University of California at Los Angeles found that lifting the long-standing ban could increase the total annual supply of donated blood by between 2 and 4 percent, adding as many as 615,000 pints per year. A shift from the full ban to a 12-month deferral that FDA opted for on Monday could add about 317,000 pints a year, the study found.

The policy that FDA discarded on Monday dates to 1983, when federal regulators banned any man from donating blood if he'd had sex with another man -- even once -- since 1977. The policy came about during the early days of the AIDS crisis, when little was known about HIV and alarmed public health officials were looking for ways to halt its spread and protect the nation's blood supply.

As screening for HIV in donated blood became standard, calls increased for FDA to lift the ban. In 2010, then-U.S. Sen. John F. Kerry and 17 of his colleagues wrote to FDA, saying that “healthy blood donors are turned away every day due to an antiquated policy and our blood supply is not necessarily any safer for it.” Then last year, the American Medical Association urged a change, with one board member labeling the ban “discriminatory.”

FDA officials said Monday that they examined a range of scientific studies, epidemiologic data and shared experiences from other countries that have revised their own donation policies for gay and bisexual men. The agency also considered hundreds of comments on its proposal in recent months.

Peter Marks, deputy director of FDA’s Center for Biologics Evaluation and Research, told reporters Monday that the agency considered a range of approaches, but ultimately settled on the 12-month deferral window because it was backed by the most scientific evidence, and other large countries had adopted a similar approach. But he also called the change a "first step," saying the FDA will continue to conduct research and evaluate new data that emerges after the new approach goes into effect.

"We fully expect," Marks said, "that the policy put for forward in this guidance will continue to evolve."

The FDA said that it expects the changes "will maintain or improve blood safety with respect to HIV" and noted that a similar update was made in 2000 in Australia, where the epidemiology of HIV is similar to the United States, and there were no observable adverse effects associated with the change.

This post has been updated.

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