U.S. Sen. Elizabeth Warren is criticizing what she's says is the sluggish pace the nation's top health officials have taken at reevaluating blood donation policies for gay men.

The Massachusetts Democrat has sent a letter to Health and Human Services Secretary Kathleen Sebelius expressing those concerns and requesting information about the agency's ongoing efforts to review the policy.

 Warren said she began pushing for the change after receiving a letter from a constituent who said he wasn't allowed to give blood after the Boston Marathon bombing because of his sexual orientation.

 Warren called the practice discriminatory and said blood donation policy should be based on science.

 Under current regulations, men who have sex with other men are banned from donating blood for life, a policy put in place during the AIDS epidemic in the 1980s.

 The letter points out that the American Medical Association has adopted a resolution opposing the Food and Drug Administration's lifetime ban on blood donations by gay men.

 The organization said the FDA should instead focus on individual risk factors rather than just sexual orientation.  Opponents of the policy also say it needlessly turns away

 healthy blood donors at times when blood donations are needed.  (Associated Press)