What Is a Screening Mammogram?

A mammogram is an X-ray test of the breast (mammary glands) used to screen for breast problems, such as a lump.

Why Is It Done?

A mammogram is done to help screen for or detect breast cancer. Many small tumors can be seen on a mammogram before they can be felt by a woman or her health professional.

Mammograms do not prevent breast cancer or reduce a woman's risk of developing cancer. However, regular breast cancer screening can reduce a woman's risk of dying from breast cancer by detecting it in its early stages.

What Is the Difference Between a Screening Mammogram and a Diagnostic Mammogram?

According to the American Cancer Society, a screening mammogram is used when the patient does not have any concerning symptoms such as a lump in the breast, nipple discharge or breast skin changes. This exam usually consists of two standard images of each breast and should be part of a routine screening for women, starting at age 40.

Along with offering 3-D screening mammograms at all locations, Memorial Hermann also offers the SmartCurve system for 3-D screening mammograms at some locations. This technology provides a curved compression surface for a more comfortable patient experience. Your mammography technologist will confirm if you are a candidate for Smart Curve during your screening appointment.

A diagnostic mammogram is performed to provide radiologists with a more in-depth picture of problems, changes or concerning symptoms. A diagnostic mammogram can also be used for a patient that was previously treated for breast cancer. These X-rays consists of two standard images of each breast plus more focused images of the area(s) of concern. The additional pictures allow for more accurate and effective characterizations of the symptom.

Screening Mammography Recommendations for Women Receiving the COVID-19 Vaccine

Some women who receive the COVID-19 vaccine develop swollen lymph nodes under their arm on the same side as their vaccine injection. This is a normal immune reaction to the vaccine. These swollen lymph nodes usually return to normal on their own in a few days or weeks. 

Swollen lymph nodes under one arm can be seen on a mammogram and can be a rare sign of breast cancer. Depending on your medical history and when you received your vaccine, the breast radiologist may recommend that you return for additional imaging of your underarm area.

While both your annual screening mammogram and COVID-19 vaccine are very important to staying healthy, delaying your vaccine is not recommended even if your screening mammogram is due or scheduled.

How Do I Prepare for a Screening Mammogram?

On the day of your mammogram, do not use any deodorant, perfume, powders or ointments on your breasts. The residue left on your skin by these substances may interfere with the X-rays.

If you are still having menstrual periods, you may want to have your mammogram done within two weeks after your menstrual period ends. The procedure will be more comfortable, especially if your breasts become tender during this time.

Comparison with prior imaging is key to assessing for change and accurate diagnosis. Please bring a CD of your prior studies if your prior breast health studies were performed outside of Memorial Hermann. If you need us to request your prior films from another facility, please complete a medical release of information form and return it to our facility prior to your appointment. Once received, we will request the films.

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Mammogram Reminder

Early detection is the best defense against breast cancer, which is why Memorial Hermann can send you a reminder to schedule your annual screening mammogram.

Remind Me

How Is It Done?

A mammogram is done by a radiology/mammogram technologist. You will need to:

  • remove any jewelry that might interfere with the X-ray picture
  • remove your clothes above the waist; you will be given a cloth or paper gown for the test.

If you are concerned about an area of your breast, show the technologist so that the area can be noted. You usually stand during a breast cancer screening; sometimes you may also be asked to sit or lie down, depending upon the type of X-ray equipment used. One at a time, your breasts will be positioned on a flat plate that will acquire the image. Another plate compresses your breast tissue. Very firm compression is needed to obtain high-quality pictures.

You may be asked to lift your arm or use your hand to hold your other breast out of the way. For a few seconds while the X-ray picture is being taken, you will need to hold your breath. Usually at least two pictures are taken of each breast, one from the top and one from the side.

How Long Does It Take?

You may be in the mammogram clinic for up to an hour; the mammogram itself takes about 10 to 15 minutes. You will be asked to wait; usually about 5 minutes; until the X-rays are developed, in the event repeat pictures need to be taken.

In some clinics and hospitals, X-ray pictures can be viewed immediately on a computer screen (digitally).

How Does It Feel?

The X-ray plate will feel cold when you place your breast on it. Having your breasts flattened and squeezed is usually uncomfortable. However, it is necessary to flatten out the breast tissue to obtain the best images.

What Happens After the Test?

A radiologist will interpret your exam. The technologist who administers the test cannot interpret or discuss what they are viewing while performing the exam. A report will be sent to your physician's office to discuss results.

Make an Appointment

Schedule a routine screening mammogram online 24/7.

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