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What is a mammogram?

A mammogram is an x-ray picture of the breast. Health care providers use mammograms to look for early signs of breast cancer. There are two types of mammograms: screening mammograms and diagnostic mammograms.

What is a screening mammogram?

A screening mammogram is a mammogram usually done for women who have no signs or symptoms of breast cancer. Regular screening mammograms can help reduce the number of deaths from breast cancer among women ages 40 to 74. This is because they can find breast cancer early and treatment can start earlier, maybe before it has spread.

But screening mammograms can also have risks. They 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 provider about the benefits and drawbacks of mammograms. Together, you can decide when to start and how often to have a mammogram.

Not much is known about breast cancer risk in transgender people. If you are transgender, talk to your provider about your risk and whether you need screening mammograms.

What is a diagnostic mammogram?

A diagnostic mammogram is done for people who have a lump or other signs or symptoms of breast cancer. The signs can include breast pain, thickening of the skin of the breast, nipple discharge, or a change in breast size or shape. But these signs can also be caused by a breast condition that is benign (not cancer). A mammogram, along with other tests, can help your provider figure out whether you have cancer.

How is a mammogram done?

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 will get both breasts x-rayed from the front and from the side. Afterwards, a radiologist (a doctor with special training) will read the mammogram. The doctor will look at the x-ray for early signs of breast cancer or other problems. You will usually get the results within a few weeks, although it depends on the clinic or medical office that you went to. If your results are not normal, you should hear back earlier. Contact your provider or the office where you had the mammogram if you do not receive a report of your results within 30 days.

What happens if my mammogram is not normal?

An abnormal (not normal) mammogram does not always mean that there is cancer. You will need to have additional mammograms, tests, or exams before your provider can tell for sure. You may also be referred to a breast specialist or a surgeon. But it does not necessarily mean you have cancer or need surgery. You would see one of these doctors because they are experts in diagnosing breast problems.