Mammography is a specific type of breast imaging that uses low-dose x-rays to detect cancer early—before women experience symptoms—when it is most treatable.

Mammography plays a central part in the early detection of breast cancers because it can show changes in the breast up to two years before you or your physician can feel them.

Like all X-rays, mammograms use doses of ionizing radiation to create images. These images are then analyzed for any abnormal findings.

Screening mammography is the type of mammogram that checks you when you have no symptoms. It can help reduce the number of deaths from breast cancer among women ages 40 to 70. But it can also have drawbacks. Mammograms can sometimes find something that looks abnormal but isn’t cancer. This leads to further testing and can cause you anxiety. Sometimes mammograms can miss cancer when it is there. It also exposes you to radiation. You should talk to your doctor about the benefits and drawbacks of mammograms. Together, you can decide when to start and how often to have a mammogram.

Mammograms are also recommended for younger women who have symptoms of breast cancer or who have a high risk of the disease.

When you have a mammogram, you stand in front of an x-ray machine. The person who takes the x-rays places your breast between two plastic plates. The plates press your breast and make it flat. This may be uncomfortable, but it helps get a clear picture. You should get a written report of your mammogram results within 30 days.