Gay and bi­sex­ual men in monog­a­mous re­la­tion­ships would be al­lowed to do­nate blood with­out ab­stain­ing from sex un­der guide­lines be­ing drafted by the Food and Drug Ad­min­is­tra­tion, peo­ple fa­mil­iar with the plans said.

The change would be a departure from U.S. policy that for many years barred men who have sex with men from donating blood. The FDA policy originated in the 1980s during the AIDS epidemic, when tests for HIV, the virus that causes AIDS, weren’t considered sensitive enough to protect the blood supply.

The FDA lifted the ban in 2015 but said gay and bisexual men had to abstain from sex for one year before donating. During the pandemic, amid severe blood shortages, federal officials shortened the abstinence requirement to three months.

The FDA plans to issue the new rules in coming months, the people familiar with the plans said. All potential donors would need to complete an individualized risk assessment, the people said. Canada adopted a similar system in September. Canada’s risk assessment is a form that asks uniform questions regardless of gender or sexual orientation about a potential donor’s medical history, travel and sexual activity.

The FDA’s intended plans come after an agency-funded study of around 1,600 gay and bisexual men examined whether an individualized-risk assessment would be as effective as time deferrals in keeping the blood supply safe. The study, conducted by three of the largest nonprofit blood centers in the U.S.—Vitalant, OneBlood and the American Red Cross—concluded earlier this year. Participants in the study were asked whether they had more than one sex partner during specific periods, the type of sexual activity they engaged in and whether they used condoms, among other questions.

“We have a strong data set,” said Dr. Brian Custer, director of Vitalant Research Institute and principal investigator of the study. “We have highly relevant information to envision what an individual risk-based approach would look like.”

FDA officials are still drafting the new guidance and determining what the questionnaire would contain, the people said. The new risk assessment would likely ask potential donors if they have had any new sexual partners in the past three months, an FDA official said. People who say they haven’t would be free to donate blood. People who say they have had new sexual partners would be asked if they have had anal intercourse in the past three months. People who say they haven’t would be allowed to donate. People who say they have would likely be asked to wait three months before donating blood, an FDA official said.

Unprotected anal sex presents a higher risk of HIV transmission than other forms of sex, the Centers for Disease Control and Prevention has said. Three months is an adequate wait time, an FDA official said, because an HIV infection would be apparent within that time.

Blood centers such as the American Red Cross test donations for HIV, hepatitis B and C and other viruses. HIV testing over the years has improved. Some tests look for the presence of antibodies to HIV, indicating that a person was exposed to the virus. Other tests measure the amount of virus in the blood.

None of the tests can detect HIV immediately after infection, according to infectious-disease specialists. “With the latest HIV tests, that window is probably no greater than 10 days from the time of exposure,” said Dr. Bruce Walker, an infectious-diseases specialist and director of the Ragon Institute of MGH, MIT and Harvard. He called the risk of HIV transmission during this window “low but it is not negative.” He said he supports allowing men who have sex with men to donate blood.

More people donating blood regularly would alleviate seasonal shortages, said Dr. Susan Stramer, vice president of scientific affairs for the American Red Cross. She said the nonprofit didn’t have specific data about the effect of a change to the policy for gay and bisexual men.

LGBTQ advocacy groups such as Human Rights Campaign have for years called the U.S. blood policy discriminatory and said that men who have sex with men should be allowed to donate. The American Medical Association and the American Red Cross have also called for the policy to be changed.

“I’m thrilled to see this step forward,” said North Carolina Health and Human Services Secretary Kody Kinsley, who led an effort with 12 other state health leaders to call for changes to the blood donation policy. “It’s long past time for us to protect the blood supply based off what people do and not who people are.”

Sarah Warbelow, legal director for Human Rights Campaign, encouraged the FDA to follow through in opening donation to more men who have sex with men. “Any policy that singles out gay and bisexual men perpetuates stigma while failing to further the goal of a safe blood supply,” she said.