The U.S. Department of Health and Human Services (HHS) said this week that it would review its decades-old policy of banning blood donations from homosexual and bisexual men, drawing praise from advocacy groups which call the prohibition discriminatory and lacking in scientific basis.

The ban was introduced in 1983, at the height of the AIDS epidemic, as an attempt to safeguard blood supplies from potential contamination. Since that time, techniques have been developed to screen blood for HIV, AIDS and numerous other diseases.

In spite of the HHS announcement -- sparked by an inquiry from Sen. John Kerry (D-MA) -- officials said they would not be able to reconsider the ban for another two years, at which point the policy would be reviewed if the necessary research is funded by Congress.

"We are pleased to see that the federal government has taken critical steps to review outdated blood donation policies," Nathan Schaefer, director of public policy for the advocacy group Gay Men's Health Crisis, said in a media advisory. "As this research agenda is pursued, GMHC will continue educating the public about the negative consequences of current blood donation policies, and advocating for revised policies that would allow low-risk gay men to donate blood and maintain the highest standard of blood safety."

"We are encouraged by the Secretary's proposed research agenda," Mark Skinner, President of the World Federation of Hemophilia, added in the same release. "The knowledge gained will allow for a thoughtful scientific review of the suboptimal aspects of the donor deferral policy."

The U.S. Food and Drug Administration admitted last year that its blood donation policies were flawed and called for fresh research, but declined to lift the ban on homosexuals.