What Is a 3D Mammogram?

A 3D mammogram is a low-dose X-ray used to take images of the inside of the breast. Like a standard mammogram, it can be used to screen for breast cancer or identify the cause of other breast symptoms. From the perspective of the person being screened, the procedures feel relatively similar.

One difference, however, is that more images are taken with the 3D mammogram than the standard procedure. It takes multiple, thin X-rays from different angles so that when the image slices are viewed together, a three-dimensional (3D) image is created.

This more detailed view may make it less likely that someone would need to return for additional testing should anything abnormal be identified in an image.

The tradeoffs of getting a 3D mammogram include a higher cost (there might be a higher co-pay or it may not be covered by insurance), increased radiation exposure (if not using newer low-dose 3D mammography), and a longer time to receive results. Because of these, some experts question the benefits of 3D mammograms over regular mammography.

3D mammography is also called digital breast tomosynthesis (DBT). DBT may be performed alone or in combination with other types of mammography.

Purpose of 3D Mammograms

The purpose of 3D mammograms is to screen for breast cancer. Breast cancer screening guidelines are somewhat controversial, and different professional organizations recommend different frequencies and ages for how early screening should start.

In general, screening guidelines are designed to balance the benefits of screening with the risks. Benefits of screening include earlier detection of cancers, which may make them easier to treat. Risks include exposure to radiation and overtreatment.

Currently, no screening guidelines explicitly recommend the use of 3D mammography over standard, 2D mammography. Also, 3D mammography is not available in all areas, and it may be a somewhat more expensive procedure.

Because it takes images from multiple angles, there is a possibility that a 3D mammogram may reduce the need for additional imaging. And it may make it easier to identify certain types of breast changes, especially in women with dense breasts. This may be particularly true in combination with 2D mammography.

Some experts say there is a risk of overdiagnosis and treatment as smaller anomalies may be detected that would not have been life-threatening). However, a study published in 2020 found that 3D mammography had significantly fewer false positive results. Patients may be exposed to more radiation than when getting a 2D image if not using newer low-dose 3D imaging.

Risks and Contraindications

Several potential risks of mammography have been identified and include:

• False-positive tests
• Pain or discomfort
• Overdiagnosis and treatment of cancers that would not have had a health impact
• Radiation-induced cancer (extremely rare)

It is unclear how the risks of 3D mammography compare to those of 2D mammography. Radiation exposure is higher where 3D mammography is combined with 2D mammography. However, the overall risk of radiation-induced cancer is still extremely low.

Contraindications

There are no absolute contraindications (reasons not to have the screening) for 2D mammography, and contraindications for 3D mammography are similar.

That said, in general, people with suspected cancer or symptoms that could be cancer-related should not be screened with mammography alone. They should undergo diagnostic testing, including ultrasound.

If you are pregnant you are generally advised to delay screening mammograms until after your pregnancy. However, it is appropriate to use mammography, with dose-reduction techniques, for people with suspected pregnancy-associated breast cancer.

People who are lactating should discuss with their doctors the potential advantages of pumping or breastfeeding before screening.

If you have breast implants, let your doctor and radiologist know about the implants prior to mammography as the presence of implants can affect technique.

Before the Test

As stated, there is some disagreement among professionals about when it is appropriate to start mammography and how frequently people should have mammograms. It is important to discuss your risk factors with your doctor and engage in shared decision-making to determine the screening frequency that makes the most sense for you.

Factors that may affect your decisions about when to start mammography, what type of mammography to have, and how often to be screened include:

• Family history of breast cancer
• Breast density
• Presence or absence of breast symptoms
• Availability of different types of screening

If your doctor is recommending a 3D mammogram, you should be certain to discuss any additional costs that may be associated with the procedure when compared to traditional mammography. Not all insurance policies cover 3D mammography.

If you are having difficulty deciding between a 3D and a 2D mammogram, it may help to ask what percentage of people are asked to come back for additional imaging. The benefits of 3D mammograms may be higher in centers with a high rate of recall after 2D mammograms.

If you have decided to undergo a 3D mammogram you will usually need to schedule it in advance. You may also be offered a 3D mammogram when you go in for a 2D mammogram. Before accepting, be certain to ask about any additional cost and time requirements.

Timing

In most facilities, you should expect to be able to get in and out within 30 minutes. The actual mammogram usually only takes around 10 minutes.

You may spend a bit more time in the waiting room and filling out paperwork. Some imaging centers may allow you to fill out forms in advance, which can save you time on the day of testing.

If you menstruate, consider scheduling this test for the week after you have finished your period. That is when your breasts are least likely to be tender.

Location

3D mammography may be performed in a hospital or at an outpatient clinic. Not all mammography locations offer 3D imaging. Therefore, if you are interested in 3D mammography, check with the center before booking.

What to Wear

You will generally be asked to undress from the waist up and remove all metal on your upper body. Therefore, it can be helpful to wear a two-piece outfit and skip any jewelry. You will be given a gown to put on and should wear it with the opening in the front.

You should avoid wearing deodorant, lotion, perfume, and powder or you will be asked to wipe it off before the test.

Food and Drink

There are no food or drink restrictions before a mammogram.

Cost and Health Insurance

Although insurance companies routinely cover 2D mammography, they may or may not cover 3D mammography. If you are considering a 3D mammogram, check with your insurance company and the screening center about any additional cost to you.

Some insurers require referrals and prior authorization for mammography. Others do not.

What to Bring

You should bring your health insurance card with you to the testing center. Other than that, you do not need to bring anything special. You will be able to drive yourself home or take other modes of transportation without restriction as you will not receive any anesthesia.

During the Test

When you first arrive for the test, you will likely be asked to fill out paperwork about your health history. You will then be asked to remove all clothing and jewelry above your waist. At this time, you will also be asked to wipe off any deodorant or powder and be given a gown to put on.

Throughout the Test

You will be asked to stand in front of the mammography machine. The technician will position one of your breasts on a platform and help you position your head, arm, and torso. A plastic plate will then press your breast against the platform. This may be uncomfortable, but if it becomes too painful, tell the technician.

Once your breast is in place, the technician will turn on the machine. It will move from side to side in an arc to take multiple pictures of your breast. You may be asked to hold your breath.

After the first round of pictures is taken, a second round may be taken from a different angle (i.e., from the top and then the side.) For this, your breast may be repositioned on the plate. Once the first breast has been imaged, the procedure will be repeated with the second breast.

The entire process should take around 10 minutes.

Post-Test

Once the images are complete, the technician will check that they are clear. Then you will be allowed to get dressed. You can usually leave the testing center as soon as the test is complete.

After the Test

Before leaving the testing center, you may want to ask how long it usually takes to receive results. It may take longer to receive the results of a 3D mammogram than for a 2D mammogram as the radiologist has more images to look through. You may receive your results either from the radiologist or from your doctor.

Not all doctors report negative results (those revealing no significant or noticeable abnormality). Some people find that it helps to reduce their anxiety if they ask in advance whether they will hear about mammogram results either way.

You may feel some discomfort after a mammogram, but this is usually minor. People with larger breasts may want to consider wearing a bra that does not have underwire after the procedure to reduce any discomfort. Lingering pain is rare and usually mild.

If you have soreness, pain, or bruising more than 24 hours after your mammogram, you should discuss those symptoms with a healthcare provider.

Interpreting Results

Mammogram results usually come back within two weeks. Some centers may be able to get them back substantially faster. However, 3D mammograms may take slightly longer to read than 2D mammograms. It is a good idea to ask your technician how long it usually takes for results to come back from their center.

Mammogram results may contain descriptions of breast density as well as both benign (unproblematic) and other types of breast changes. Although some states require doctors to let patients know that they have dense breasts, having dense breasts is not in and of itself a problem. Breast density can make reading a mammogram more difficult, however, and may affect overall cancer risk.

Your results will describe any findings and also include a BI-RADS number. This number indicates the likelihood that your mammogram findings are cancerous. Higher numbers indicate a greater suspicion of breast cancer and may indicate a need for shorter follow-up. For example, a 3 means that your breasts are probably healthy, but you should return for a follow-up in six months.

Follow-Up

You may need to undergo follow-up imaging if there are suspicious findings or a problem with the image. Follow-up imaging is less likely to be needed after 3D than 2D mammography.

If a suspicious area is seen on your mammogram, you may also be referred for a biopsy. A biopsy removes a sample of breast tissue so that it can be tested for cancer.

Ultimately, follow-up will vary substantially depending on your results. If any abnormalities are found, it is important to discuss next steps with your doctor.

A Word From Verywell

There is not yet sufficient evidence to conclusively show that 3D mammograms are that much better than 2D mammograms to be worth the additional cost. Although the technology is promising, it is still reasonable to decide not to undergo a 3D test—particularly if any associated fees would present a hardship.

That said, people who are particularly concerned about needing to return for additional images may value the reduced recall rates for a 3D test and may be pleased to know that more and more insurance companies are covering 3D exams.