About 35 percent of women get annual mammograms from age 40 onward. But the value of those screenings has been much debated, because mammograms for people in their 40s catch relatively few cases of breast cancer, generate plenty of false positive results, and produce some cases of unnecessary treatment. Thus, while some organizations have advocated for testing to start at age 40, in 2009 the U.S. Preventive Services Task Force recommended that women start regular mammogram screening at age 50, not age 40 — a major preventative health policy change….
