Citing a "possible," and as yet unproven, link between the anthrax vaccine and birth defects, experts at the US Department of Defense are advising that servicewomen not receive the shots during pregnancy.

Assistant Secretary of Defense Dr. William Winkenwerder on January 16 sent a memo to top officials of the US Army, Navy and Air Force, requesting that they "strengthen the screening of females of childbearing age with careful questioning or other positive efforts, potentially including pregnancy testing when appropriate, to prevent the administration of vaccine to pregnant women."

Preliminary data from a study by the Naval Health Research Center of women who have received the anthrax vaccine has "identified a possible relationship between maternal anthrax vaccination in the first trimester and higher odds of birth defects," according to a statement from the Defense Department.

This week's announcement adds to the controversy surrounding the military's use of the anthrax vaccine, which predates by several years this fall's recent spate of germ-tainted mail.

Many experts believe the vaccine to be both ineffective and potentially harmful to recipients, and even top US government health officials concede there is currently not enough data available to make a firm recommendation that those at risk of anthrax exposure receive the vaccine.

Spurred by the threat of bioterrorism during the Gulf War, the Department of Defense originally proposed to vaccinate all 2.4 million members of the military. However, the program met with considerable resistance, including a number of soldiers who elected to face disciplinary action rather than receive the vaccine.

Following this fall's mail scares, the government's policy for civilians has been to make the vaccine available to potentially exposed individuals who have been thoroughly informed of existing data on the vaccine. Individuals who decide to get the shot are then asked to sign an informed consent document prior to administration.

According to Dr. Anthony Fauci, head of the National Institute for Allergy and Infectious Diseases, officials should now be prepared "to just say 'we don't know the answer'" when it comes to the anthrax vaccine. At the same time, he said, "the American public must learn to accept and deal with risks that unfortunately are going to be with us for a long period of time."

Reuters New York January 18, 2002