The days of yearly mammograms beginning at age 40 might be numbered. An American health panel that guides doctors, insurance companies and policymakers says breast cancer screening should begin at age 50—and that when it does begin, mammograms should be conducted every two years instead of every year. What about self exams? Doctors should stop teaching women to do them, the group insists. The new recommendations by the United States Preventive Services Task Force represent a startling about-face. Just seven years ago, the group pushed for yearly mammograms beginning at age 40, and remained neutral on the issue of breast self-examinations. The reason behind the switch, says task force vice chairwoman Dr. Diana Petitti, is new data on the harm of overscreening, which can lead to further tests, unnecessary biopsies, and extreme anxiety. Nearly two thirds of American women in their 40s had mammograms in the last two years.