Found Out You Have Dense Breasts? Here’s What Doctors Say to Do Next

Getting a “normal” mammogram result should be a relief. You made the appointment, got through the uncomfortable breast compression, and waited for someone to tell you everything looked okay. But what if somewhere in that reassuring letter, you read that you have “dense breasts,” a factor that can make cancer harder to detect and increase your risk of developing it?

It’s a question more and more women are asking. Since September 2024, federal regulations have required mammography facilities to tell patients if their breasts are dense. The letter gives you information worth knowing, but it doesn’t necessarily tell you what to do next.

Dense tissue is common—it’s found in about half of women ages 40 and older. However, it doesn’t mean something abnormal was found, says Bhavika Patel, M.D., a professor of radiology at Mayo Clinic in Arizona. “A density notification should start a conversation, not create panic,” she says. Here’s how to have that conversation with your health care provider—and come away with a plan you understand.

In 2025, scientists behind a study called the BRAID trial asked a practical question: If a mammogram doesn’t show cancer in a woman with dense breasts, which additional test is best at finding something it missed?

The researchers studied women ages 50 to 70 in the UK who had dense breasts and normal 2D mammograms. A total of 6,305 women completed additional screening and the results were compelling: Contrast-enhanced mammography (a mammogram performed after an injection that helps cancer stand out) found about 19 cancers per 1,000 scans. A shortened version of a breast MRI found about 17. Automated ultrasound, which scans the whole breast, found about four.

The cancers found with contrast-enhanced mammography and MRI were also smaller, on average, than those found with ultrasound, explains BRAID lead investigator Fiona Gilbert, M.D., a professor of radiology at the University of Cambridge. That’s promising, because finding a cancer while it’s still small can give doctors a chance to treat it earlier.

But these results came from the first round of extra screening. The study didn’t establish whether adding those tests helps women live longer, or how many cancers that were found might never have caused harm during a woman’s lifetime. And, because the participants were ages 50 to 70 and had 2D mammograms, the findings don’t tell us what to expect for younger women or those already getting 3D mammograms.

Whether one of these additional tests would be useful for you starts with understanding your density and your overall risk. Your breasts are made up of a mix of fat, milk-producing glands, ducts, and tissue that helps hold everything in place. On a mammogram, fat shows up dark, while the other tissue looks white. The more of that white tissue you have, the denser your breasts are. The tricky part is that many breast cancers also look white, so they can be harder to spot against that background.

“Breast density is a description of how the breast looks on a mammogram; it is not a diagnosis or a measure of how healthy your breasts are,” says Janie Grumley, M.D., a breast surgical oncologist and director of the Margie Petersen Breast Center’s comprehensive breast program at Providence Saint John’s in Santa Monica, California. Density also raises breast cancer risk separately from its ability to hide a cancer on an image.

When a radiologist reads your mammogram, they put your breast density into one of four categories, ranging from mostly fatty to extremely dense. The two denser categories are the ones that matter if your letter says you have “dense breasts.” “Heterogeneously dense” means there are patches of dense tissue mixed with fat—about 40% of women age 40 and older have this. “Extremely dense” means dense tissue makes up most of the breast, which can make cancer even harder to see—about 10% of women age 40 and older have this.

If your mammogram is normal and you have no new breast symptoms, a density notification alone isn’t an emergency, Dr. Grumley says. It’s merely a reason to contact the provider who manages your screening. According to Dr. Grumley, the most useful next question is “What is my personal breast cancer risk, and does it change how I should be screened?”

Olivia Munn’s experience is a widely known example of what a risk assessment can change. Despite a normal mammogram and negative genetic testing, her OB-GYN, Thaïs Aliabadi, M.D., calculated her lifetime breast cancer risk at about 37%. That prompted an MRI, followed by more imaging and biopsies that diagnosed cancer. The risk assessment itself didn’t find the cancer, but it did give her doctor a reason to look further.

To assess your risk, your doctor will consider your mammogram report along with your age, previous breast biopsies, genetic testing, and family cancer history. If breast cancer runs in your family, your doctor will want to know who had it, how old they were when they were diagnosed, and if they tested positive for one or more genetic strains.

Keep in mind your risk may change over time. For instance, breast density often decreases after menopause, and hormone therapy can affect it, Dr. Patel says. A new cancer diagnosis in your family or a change in your own medical history may also mean it’s time to revisit your screening plan. “Screening should evolve as the woman and her risk factors evolve,” she says.

This is where you may hear different advice, even from specialists. They don’t all agree on how much breast density alone should influence the decision. Ask your doctor what they factor into their recommendation and what another test would add.

Karla Kerlikowske, M.D., a professor of medicine and epidemiology/biostatistics at the University of California, San Francisco, recommends looking at a woman’s risk of developing advanced breast cancer using the BCSC risk calculator. In her approach, dense breasts alone aren’t enough to recommend additional screening; she considers it for women at high risk of advanced cancer.

Wendie Berg, M.D., Ph.D., a breast imaging researcher at UPMC and the University of Pittsburgh, puts more weight on density. She recommends additional screening for all women with extremely dense breasts. For heterogeneously dense breasts, she considers other risk factors, while noting that additional screening remains an option without them.

Medical organizations differ, too. The American College of Radiology supports considering extra screening based on density and risk. The U.S. Preventive Services Task Force says there isn’t enough evidence to recommend for or against adding MRI or ultrasound for women with dense breasts and an otherwise normal mammogram. That doesn’t mean the tests don’t find cancers; uncertainty remains about their overall benefits and harms.

Your doctor may recommend one of the tests detailed below even if your mammogram is normal. If you decide to pursue one of them, check with both the imaging center and your insurance company before assuming another scan will be covered like your regular mammogram, suggests Janice Sung, M.D., a professor of radiology and associate chief of breast imaging at Columbia University Vagelos College of Physicians and Surgeons. Ask whether you need approval from your insurer beforehand, whether the center is in your plan’s network, how much you could owe, as well as what the coverage is for any follow-up scans or biopsies, too.

Dense breasts are linked to a higher risk of breast cancer and they can make breast cancer detection more difficult. Because of this, if you have dense breasts, your doctor may suggest additional screening on top of your regular mammogram.

If your doctor recommends another scan, ask why that test makes sense for you and when you should schedule it. Before booking, Dr. Berg says it’s smart to ask what would happen if the scan showed something that needed a closer look. A callback doesn’t mean you have cancer, but knowing what could come next may make it less unsettling. If the recommendation is to stick with mammograms, ask what makes that enough for now and when to check in again.

Whichever option you choose, keep your mammograms on the calendar. Richard Reitherman, M.D., Ph.D., medical director of breast imaging at MemorialCare Breast Center at Orange Coast Medical Center in Fountain Valley, California, notes that 3D mammography can improve cancer detection in dense breasts. Dr. Patel agrees, adding that, while it can’t reveal every hidden cancer, mammography finds important abnormalities, including tiny calcium deposits that other tests may miss.

Lastly, if you notice something new, whether it be a lump, a nipple or skin change, bloody nipple discharge, or another persistent breast concern, don’t wait for your next screening appointment. Let your doctor know as soon as possible, even if you recently had a normal mammogram. “A normal mammogram should not be used to dismiss a new breast symptom,” Dr. Grumley adds.