Screening for Breast Cancer: What to Expect at a Mammogram

It’s common to be nervous before your first mammogram. You’ve likely seen photos of people getting mammograms, and it’s easy to let your mind run wild about what it actually feels like. 

“For women who are anxious about having a mammogram, I think it's important to remember that once you've had that first mammogram, the anxiety will lessen with subsequent mammograms, and the benefit of having the mammogram far outweighs the risk of breast cancer death,” says Brenda Panzera, MD, oncologist at Mount Sinai Hospital and Lenox Hill Hospital.

What happens at a mammogram

At the radiology office, you will be asked to undress from the waist up. It’s helpful to wear pants or a skirt — as opposed to a dress — so you only have to remove your top. In fact, some places may give you a hospital gown that only covers your top half, so being able to wear your pants could save you some awkwardness. (Learn more tips to prepare for a mammogram.)   

Next, you will be guided to the mammogram machine, which contains two parallel plates. “The X-rays are usually performed by compressing the breast tissue [between the plates], which for some can be uncomfortable momentarily,” says Dr. Panzera.

How uncomfortable? It depends. Some people say it’s no biggie — just a little pressure. If the compression feels painful, however, speak up: Your technician can help adjust your breasts or the plates to make it more comfortable, as it’s not supposed to cause pain.

As uncomfortable as the compression may be on your breasts, it’s for a good reason. “The better compression that's achieved results in better films and a better ability to detect if there's any abnormalities,” says Dr. Panzera. The compression also helps hold the breasts still to reduce blurring on the X-ray image.

What doctors are looking for

“A radiologist is looking for many different things when they're looking at a mammogram,” says Dr. Panzera. “They are looking to see if there are any visible abnormalities on the X-ray.”

“Visible abnormalities” may include things like:

• Calcifications, or calcium deposits in the breast tissue. These are often benign, but can sometimes indicate breast cancer.

• Masses or nodules, or an area of dense breast tissue with irregular borders.

• Any changes compared to previous mammograms. “Oftentimes, that's one of the earliest signs that something may be happening is that if there's a subtle change between the two images,” says Dr. Panzera.

If an abnormality is found, you may be called back for additional X-rays or ultrasounds. Keep in mind that this does not necessarily mean you have breast cancer. In fact, around nine out of 10 of women called back after a mammogram are found to not have cancer, according to the American Cancer Society (ACS).

When mammograms are recommended

“The benefits of screening are early detection of breast cancer. Screening, however, does not come without some risks, and those risks need to be explored with that individual so that they can make a personalized decision,” says Dr. Panzera.

For people with an average risk of breast cancer, the ACS recommends breast cancer screening every year for women between the ages of 45 and 54 (although you have the option to begin screening at age 40). Those who are considered to have a high risk for breast cancer may begin as early as age 30. 

Learn more about breast cancer screening for early detection.