Why it's done

Mammograms are X-ray images of your breasts designed to detect cancers and other changes in breast tissue. A mammogram can be used either for screening or for diagnostic purposes:

• Screening mammogram. A screening mammogram is used to detect breast changes that could be cancerous in people who have no signs or symptoms. The goal is to detect cancer when it's small and treatment may be less invasive.

  Experts and medical organizations don't agree on when to begin regular mammograms or how often the tests should be repeated. Talk with your health care provider about your risk factors, your preferences, and the benefits and risks of screening. Together, you can decide what screening mammography schedule is best for you.

• Diagnostic mammogram. A diagnostic mammogram is used to investigate suspicious breast changes, such as a new breast lump, breast pain, an unusual skin appearance, nipple thickening or nipple discharge. It's also used to evaluate unexpected findings on a screening mammogram. A diagnostic mammogram includes additional mammogram images.