Mammograms can help detect breast cancer early. They help find it before it grows big enough to feel and before it has a chance to spread.

A mammogram is a low-dose X-ray of the breast. Mammography is used for routine screening for breast cancer. It’s also used for diagnostic purposes. The same machines are used for each purpose, but diagnostic mammograms usually take longer because they take more images.

Film and digital mammography have a similar ability to detect cancer, and the procedure is the same. The main difference between the two is how the files are stored, enhanced, and shared. A radiologist reads both types and sends a report to your doctor.

Continue reading to learn about the similarities and differences between 2-D and 3-D mammography.

What is 2-D mammography?

In the United States, digital mammography, or 2-D mammography, has become the norm, replacing film mammography. There’s no difference in how the procedure is performed. While you’re in a standing position, a technologist positions your breast on a small plate. Then, a clear plate presses down on the breast while the images are taken. The procedure is repeated for the other breast.

But in the case of 2-D mammography, multiple X-rays are put together to produce two-dimensional images of the breast.

Instead of being stored on large sheets of film, 2-D images are digitally recorded. That makes them much easier to store and share between radiologists, surgeons, and other doctors. Also, digital images can be lightened, darkened, and enlarged, allowing for closer inspection.

Facilities must be certified to practice mammography. They also need to have approval by the U.S. Food and Drug Administration to perform digital mammography.

What is 3-D mammography?

Three-dimensional mammography is a newer type of digital mammography. You might also hear it referred to as breast tomosynthesis. In 3-D mammography, X-ray machines take images of thin slices of the breast at several different angles from the top and sides of your breast. Computer software then reconstructs the pictures into 3-D images.

As far as the procedure goes, your breast will be positioned and compressed the same way as with any other mammogram.

How do 2-D and 3-D compare?

The procedure

There’s no difference in any physical discomfort you may have, but the 3-D test does take a few seconds longer.


3-D mammography is newer than 2-D mammography and may not be available at all mammogram facilities. Also, 3-D mammograms can cost a bit more. Some insurers may not cover 3-D mammograms, and some charge different prices.


With a 3-D mammogram, the radiologist can scroll through pictures of breast tissue one layer at a time. This makes it easier to find abnormalities. Because they provide more detail, 3-D images reduce the false-positive rate. So, it’s less likely that you’ll have to return for a second mammogram or have more testing. That can help cut down on stress and anxiety.

3-D mammography has a slightly higher cancer detection rate than 2-D mammography. A study involving three years of data found that the benefits of 3-D mammograms last over time.

If you’ve been told you have dense breast tissue, it means you have more glandular tissue than fatty tissue. Fatty tissue appears gray on a mammogram. Glandular tissue appears white on a mammogram, but so does cancer. 3-D mammography makes it easier for a radiologist to tell the difference between glandular tissue and cancer, decreasing the chances of a false positive and the need for extra testing.


Sometimes, 3-D mammography is combined with 2-D mammography. Because more images are taken, you’re exposed to more radiation. But newer 3-D-only mammography may actually involve less radiation than a 2-D mammogram.

Who needs a mammogram?

The following guidelines for breast cancer screening come from the American Cancer Society:

  • Age 40 to 44: Start annual breast cancer screening with mammograms if you so choose.
  • Age 45 to 54: Get annual mammograms.
  • Age 55 and older: Get mammograms every two years or continue yearly screening, as long as you’re in good health and are expected to live at least 10 more years.

Talk to your doctor about screening for breast cancer. If you’re at a higher risk of developing breast cancer, you may be advised to start screening earlier or more frequently. This may be the case if you have a strong family history of cancer or carry certain genetic mutations, such as BRCA1 and BRCA2.

It’s safe to have either type of mammogram if you have implants, but it’s important that you inform your doctor and the technician that you have them.

Before scheduling your mammogram, find out which types your local facility offers and if your health insurance will cover the cost.

Ask when you can expect your doctor to have the results. Follow up if you don’t hear back in the expected time frame.

Between mammograms, inform your doctor of any lumps or other changes to your breasts.