The U.S. Food and Drug Administration has overturned a 30-year ban on blood donations from gay and bisexual men.
Under a new policy announced Monday, the FDA will allow donations from gay and bisexual men 12 months after their last sexual encounter with another man.
"The FDA reviewed its policies regarding HIV transmission through blood products to determine appropriate changes based on the most recent scientific evidence," the agency said in a statement.
The new policy is similar to that of several other countries, including Britain, France, Australia and Japan.
"In reviewing our policies to help reduce the risk of HIV transmission through blood products, we rigorously examined several alternative options, including individual risk assessment," said Peter Marks, deputy director of the FDA's Center for Biologics Evaluation and Research.
"Ultimately, the 12-month deferral window is supported by the best available scientific evidence, at this point in time, relevant to the U.S. population."
The FDA says potential donors with hemophilia or related clotting disorders are still barred from donating "for their own protection, due to potential harm from large needles used during the donation process."
The FDA says its policies have reduced the HIV transmission rates from blood transfusion from 1 in 2,500 to 1 in 1.47 million.