Although yearly mammograms may increase the rates of breast cancer diagnoses, a new study shows that they may not prevent breast cancer related deaths, the Los Angeles Times reports. The study, published in BMJ, “examined the medical records of 89,835 women…between the ages of 40 and 59.” Half of the women received yearly physical exams while the other half also had yearly mammograms for five years. Researchers found that while the women who received mammograms were more likely to be diagnosed with breast cancer, the rates of death between the two groups did not differ. They also found that 22% of the cancers found through mammograms were “over-diagnosed,” meaning these women received unnecessary cancer treatment. Experts say that the study made a compelling case for the reconsideration of current policies on mammography.