Breast Health FAQs

One of the best tools we have in the fight against breast cancer is screening mammography, which has helped reduce breast cancer mortality in the U.S. by nearly 40 percent since 1990. Mammography saves lives – read on to find out what you need to know.

General mammography

What is a traditional (bilateral) screening mammogram?

A traditional screening mammogram is an imaging test that looks for breast cancer in women who are considered at average risk for the disease and who have no signs or symptoms. Screening mammograms usually involve two or more low-dose x-ray pictures of each breast.

What is a 3D mammogram?

A 3D mammogram (also known as breast tomosynthesis) is a screening exam that involves multiple x-ray images of the breast taken from different angles. Then, a computer uses those images to create a 3D representation of the breast. The benefit of tomosynthesis is that it separates overlapping tissues, making it easier to see abnormalities. Almost all of our screening mammograms are performed as 3D mammograms these days.

What is a diagnostic mammogram?

While a screening mammogram looks for breast cancer in women with no symptoms, a diagnostic mammogram is meant to evaluate women who have clinical symptoms (like a lump) or to look more closely at something that is seen on a screening mammogram. Diagnostic mammograms involve different x-ray pictures than the standard images taken during a screening mammogram. A diagnostic evaluation may also include an ultrasound. You will get the results of your diagnostic mammogram before you leave the facility.

Why do I need a mammogram?

Screening mammograms are able to catch breast cancer early, when it’s easier to treat. Regular mammograms can lower the risk of dying from breast cancer. According to the Centers for Disease Control and Prevention, a mammogram is the best way to find breast cancer in most women of screening age.

If you’ve already noticed any changes in your breast, you may need a diagnostic mammogram to investigate the cause. Diagnostic mammograms are also used to evaluate abnormal results from a screening mammogram.

Can I have a breast ultrasound instead of a mammogram?

Breast ultrasound isn’t typically used as a screening tool for breast cancer. Instead, an ultrasound may be performed if the results of a screening mammogram were abnormal. A screening mammogram is used to look for breast cancer when there are no symptoms. A breast ultrasound, on the other hand, is used as a diagnostic tool to evaluate a problem found during a physical exam or a screening mammogram.

Breast cancer risk and screening

I don’t have a family history of breast cancer. Do I still need a mammogram?

Even if you don’t have a family history of breast cancer, the American Cancer Society (ACS) still recommends that women at average risk for breast cancer begin screening mammograms at age 40. In fact, most women who get breast cancer don’t have a family history of the disease, so it’s important to get screened annually.

When should I start getting screening mammograms? How often?

Siteman recommends that women begin annual screening mammograms at age 40. Annual screening at age 40 is also recommended for:

  • Transgender women (male-to-female), nonbinary and genderqueer patients who have used gender-affirming hormones for longer than five years
  • Transgender men (female-to-male), nonbinary and genderqueer patients whose sex assigned at birth is female who haven’t had top surgery

The mammography process

What should I do to prepare for my mammogram?

There isn’t much you need to do to prepare for your mammogram. First, try to schedule your exam for the week after your period so that your breasts won’t be as tender. If you’ve had mammograms done at another facility in the past, you’ll also want to bring those mammogram images with you. Your radiologist may want to compare the new images to the old ones to identify any changes.

On the day of your exam, don’t apply deodorant, powders, lotions, creams or perfumes, as these may interfere with imaging. You might also consider wearing a two-piece outfit so that you can keep your bottoms on during the exam.

What happens during a mammogram?

Just before your mammogram, you will be given a gown and asked to remove any neck jewelry and all clothing above the waist. You will stand in front of an x-ray machine that’s specifically designed for mammography. A technologist will place your breast onto a plastic plate. Another plate will then be lowered to compress your breast to hold it still as x-rays are taken. Images will be taken from the side as well. After images are taken of one breast, the entire process will be repeated for the other.

Why does my breast need to be compressed?

Breasts need to be compressed during mammograms to optimize the image quality and makes it easier for radiologists to see through breast tissue. It also minimizes the amount of radiation exposure to the breast.

Who will perform my mammogram?

Your mammogram will be performed by a technologist called a mammographer. They are specially trained to perform mammograms, ensuring that high-quality images are taken while minimizing the amount of radiation exposure.

At Siteman, all radiology technologists have advanced certification in breast mammography and have undergone rigorous training in breast anatomy and physiology, positioning and compression.

Mammography results

Who will interpret my mammogram images?

Your images will be interpreted by a board-certified radiologist with expertise in breast imaging. Radiologists are physicians who are specially trained to interpret images to diagnose diseases and injuries.

Washington University radiologists are affiliated with the internationally recognized Mallinckrodt Institute of Radiology.

How does dense breast tissue affect a mammogram?

Breast density varies greatly from person to person. Some breasts have almost all fatty tissue, while others have extremely dense tissue with very little fat. The denser the breast, the harder it can be to see masses or other findings on a mammogram. This is because both dense breast tissue and masses appear as white areas on images.

If you have dense breasts, you still need regular mammograms. While dense breast tissue can make it difficult to see cancer, most breast cancers can still be seen on a mammogram. And, according to the ACS, women who have dense breasts are at higher risk for breast cancer, so it’s especially important to keep up with regular screening.

Who will see the results of my mammogram?

After the radiologist interprets your images, they will send your results to you. They will also send your results to your primary care or referring physician, who will go over your results with you.

What are the next steps if my results are abnormal?

While getting called back after a screening mammogram can be scary, it’s actually quite common. Most women who get called back don’t have cancer. In fact, fewer than one in ten women who are called back for follow-up testing end up having cancer.

Follow-up tests that may be used to rule out cancer include a diagnostic mammogram, a breast ultrasound or an MRI. Based on the results of your follow-up test, you may need a biopsy to confirm a diagnosis.

Mammography safety concerns

Can I get a mammogram if I have breast implants?

Yes! If you have breast implants, you should still get screened regularly according to breast cancer screening recommendations. It’s important to tell your technologist if you have breast implants before your exam begins. Both silicone and saline implants can make it difficult for the radiologist to see breast tissue. For this reason, women with implants have four extra images taken in addition to the four standard mammogram images.

Can I get a mammogram if I’m pregnant?

Yes, mammography can be performed during pregnancy. The risk of radiation to the fetus is extremely low. A lead shield is placed over the belly to keep radiation from reaching the womb. If you’re pregnant, or think you could be, make sure to tell your technologist before your mammogram.

If you have concerns about getting your mammogram, you can speak with your referring provider. However, experts agree that mammography during pregnancy is safe.

Can I get a mammogram if I'm breastfeeding?

Yes, you can get a mammogram while you’re breastfeeding. There is no risk to your baby/child. We do recommend that you nurse or pump immediately before your mammogram to allow for the best images. If you’re breastfeeding, make sure to tell your technologist before your mammogram.

Should I worry about the radiation dose involved in a mammogram?

The dose of radiation used during a mammogram is extremely low – lower than any other x-ray or CT scan. Mammography is very safe and special care is taken to make sure that you’ll be exposed to the smallest amount possible. The benefits of mammography outweigh any possible harm from this minimal radiation exposure.


Will my insurance cover my annual mammogram?

Almost all health insurance plans cover the cost of screening mammograms and other cancer screenings. Be sure to call your insurance carrier before getting screened to confirm that your mammogram will be covered.

Diagnostic mammograms and ultrasounds typically are not fully covered as routine preventive health, and are subject to copayment and deductibles, per your specific plan.

If you’re uninsured or underinsured and are concerned about the cost, BJC HealthCare offers financial assistance.

Learn more about insurance and cancer screenings.