Screening mammograms use low-dose X-rays to find breast cancer early, before it causes any warning signs. These tests are important for women because treatment is more likely to be successful the sooner breast cancer is detected. The chances of survival are higher, too. While national health organizations offer different breast cancer screening guidelines, everyone agrees that women should discuss the benefits and risks of mammograms with their doctors and decide together when to begin screenings and how often to repeat them.