The American Cancer Society today recommended women at average risk for breast cancer receive screening mammograms annually starting at age 45, transitioning to every two years starting at age 55. According to the new guidelines, published in the Journal of the American Medical Association, women also should have the option to begin screening between ages 40 and 44 and to continue screening annually at age 55 if they choose. The guidelines recommend women continue screening mammography as long as their overall health is good and their life expectancy is at least 10 years. Based on a review of the evidence, the ASC Guideline Development Group found benefit from screening women in their early 40s but lower risk and greater potential for harm, primarily from false positives. The guidelines do not recommend clinical breast examination for breast cancer screening among average-risk women at any age. The breast cancer screening guidelines were last updated in 2003.