Contrary to recent media reports, the use of lead shielding during routine breast exams provides virtually no benefit in the prevention of thyroid cancer and may diminish the effectiveness of mammography.

"There has been recent emphasis in the media on the use of lead aprons for women having a mammogram. In the media two types of lead aprons have been discussed--lap aprons and thyroid aprons. There is considerable scientific evidence showing that lead aprons result in only minimal dose reductions in mammography. Mammography machines are designed to ensure patient safety, incorporating internal radiation shielding, which prevents stray radiation. The use of thyroid shields is never recommended, as thyroid shields may interfere with the mammogram. The use of a lap apron is only recommended if a woman is pregnant or thinks she may be pregnant," according to the American Association of Physicists in Medicine (AAPM). "The use of thyroid shields during mammography exams is unsupported by the scientific literature, and could result in unnecessary increases in breast dose due to repeated mammography exams. Thus the use of thyroid shields is strongly discouraged," continued the organization.

In guidance to medical professionals, the AAPM also cautions that thyroid shields can obscure mammography results to the point that otherwise unnecessary follow-up tests are required.