Mammography

Mammography uses a carefully calibrated low-dose X-ray beam to create detailed images of breast tissue. Because breast tissue is mostly soft tissue — fat, ducts, and glands — the X-ray energy levels used are lower than those for imaging bone, which keeps radiation exposure minimal while still producing clear images. The entire process typically takes about 20 minutes.

There are two major applications of mammography. Screening mammography is offered on a regular schedule to women without symptoms, with the goal of finding cancer before it causes a lump or other signs. Diagnostic mammography is used when something specific needs a closer look — a palpable lump, nipple discharge, skin changes, or an abnormal finding on a screening image. Diagnostic exams often include more views and may be read while you wait.

Digital mammography has largely replaced film-based systems, and 3D mammography (digital breast tomosynthesis) is increasingly available. Tomosynthesis captures multiple thin slices of the breast from different angles, which can improve cancer detection in women with dense breast tissue and reduce false-positive call-backs. Your doctor or imaging center can help you understand which type of mammography is most appropriate for your situation.

Mammography is the only imaging tool with decades of evidence showing it reduces breast cancer deaths. Regular mammograms can detect cancers that are too small to feel — sometimes two to three years before they would become noticeable. Earlier detection generally means more treatment options, less aggressive interventions, and better outcomes.

Guidelines on when to start and how often to get mammograms vary among medical organizations, which can be confusing. Talking with your doctor about your personal risk factors — including family history, breast density, and prior biopsies — helps you develop a screening plan tailored to you. Whatever schedule you and your doctor choose, consistency matters: keeping up with regular mammography is one of the most evidence-based things you can do for your breast health.