The 411 on Mammograms


A mammogram is an X-ray exam of the breasts.


A mammogram is a screening test that helps find breast cancer at an early stage. Mammograms can find some types of cancer 1 to 2 years before you or your healthcare provider would be able to feel it. There is a better chance of curing the cancer if it is found at an early stage.

Any woman can get breast cancer. If you have risk factors, it doesn’t mean that you’ll get breast cancer. Most women have some risk factors but don’t get breast cancer. You may have a higher risk of breast cancer if:

  • You are over 60 years old.
  • You have had breast cancer before or you have had some noncancerous breast diseases.
  • You have a family history of breast or ovarian cancer, especially a mother, sister, or daughter, but also other relatives on either your father’s or mother’s side.
  • You have inherited a change in genes called BRCA1 and BRCA2. This change increases your risk for breast cancer.
  • You have had radiation therapy to the chest.
  • You drink alcohol (the more you drink, the higher your risk).
  • You are overweight after going through menopause.
  • You don’t get a lot of regular exercise.
  • You started menstruating before age 12 and/or went through menopause after age 55.
  • You never gave birth to a child or you had your first child after age 30.
  • You did not breast-feed.
  • You have taken hormone therapy with estrogen and progesterone after menopause.

Medical organizations do not agree on how often you should have a mammogram. The US Preventive Services Task Force (2009) recommends a mammogram every 2 years for women 50 to 74 years old. The American Cancer Society (2012) recommends a mammogram every year for women 40 and older. Talk to your healthcare provider about when you should start having mammograms and how often you should have them.

If you have a high risk of breast cancer, you may need to start screening earlier and may need to be screened more often. If you have a very high risk, you may want to see a breast cancer specialist.

Mammograms are also used to check lumps found during an exam. The only way to know for sure if a lump is caused by cancer is to do a biopsy, which is the removal of a small sample of tissue for testing. Some lumps, even if they are not caused by cancer, may need to be removed by surgery.

Mammograms can show a more exact location of a lump before you have biopsy or surgery to remove it.

In addition to the mammogram, other exams may include:

  • Monthly self exams of your breasts
  • Yearly exams of your breasts by your healthcare provider
  • Magnetic resonance imaging (MRI), which uses a strong magnetic field and radio waves to show detailed pictures of your breasts

You may choose not to have this exam. Ask your healthcare provider about the benefits and the risks.


Be sure your underarms and chest are clean. Don’t put any deodorants, powders, lotions, or perfumes on your underarms or chest on the day of your mammogram. These products can look like changes in your breast tissue on the mammogram.


The exam is done in your healthcare provider’s office, an X-ray clinic, or a mobile van with a mammography machine inside. It takes just a few minutes. You will be asked to take off your shirt, bra, and jewelry.

The machine has a platform for your breasts. The technologist will put one of your breasts on the platform and put an X-ray plate on the breast to press it almost flat. This may be uncomfortable while the X-ray is being taken. This is done to:

  • Even out your breast so that all of the tissue is the same thickness
  • Hold your breast still so that the image will be clear and sharp
  • Use the lowest X-ray dose possible

Two or three different views of each breast will be taken to check the whole breast.


You may need to wait a few minutes while the technologist makes sure the X-rays are clear and sharp. The X-rays will be checked by a radiologist and the results reported to your healthcare provider. Ask your healthcare provider how and when you will hear test results. You will usually get a letter from the radiologist after results have been sent to your provider.


Your healthcare provider will explain the procedure and any risks. Some possible risks include:

  • Mammograms can find small growths that are not cancer. You may need another mammogram or another procedure to see if you have breast cancer and then find out that you don’t have cancer. This can cause anxiety as you wait for results. It can also be expensive.
  • Mammograms can find very small cancers that may turn out to be harmless. These cancers may stop growing, shrink, or even go away on their own. Because it’s not possible to know if a cancer will be harmless, many providers recommend that all cancer needs to be treated.
  • Mammograms expose you to very low levels of radiation. Each time you have a mammogram or any other kind of X-ray, you are exposed to more radiation, which may be a risk for developing cancer.
  • Mammograms do not find all breast cancers. About 1 out of every 4 or 5 breast cancers are missed by a mammogram and found only when they are felt during a breast exam. If you feel a lump in your breast, report it right away to your provider even if you have had a recent mammogram that did not find any cancer.

There is risk with every treatment or procedure. Ask your healthcare provider how these risks apply to you. Be sure to discuss any other questions or concerns that you may have.

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Published by RelayHealth.
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