Skip Navigation
Search Menu
Healthy Woman

Conditions & Health

6 Mammogram Myths

Female doctor directing patient to mammography machine

Common mammogram myths you may believe could have a serious impact on your long-term health. Learn the truth about this lifesaving screening exam.

When to Get a Mammogram

Dr. Susan Harvey, director of breast imaging at Johns Hopkins, debunks a common myth about mammograms.

Think it’s not a big deal skipping your annual mammogram this year? Or are you concerned that a mammogram uses too much radiation?

A yearly mammogram for women 40 and older helps to detect breast cancer earlier, leading to less aggressive treatment and a higher rate of survival.

Myth #1: I don’t have any symptoms of breast cancer or a family history, so I don’t need to worry about having an annual mammogram.

Fact: The American College of Radiology recommends annual screening mammograms for all women over 40, regardless of symptoms or family history. “Early detection is critical,” says Susan Harvey, director of the Johns Hopkins Breast Imaging Division. “If you wait to have a mammogram until you have symptoms of breast cancer, such as a lump or discharge, at that point the cancer may be more advanced and may no longer be curable.” According to the American Cancer Society, early-stage breast cancers have a five-year survival rate of 99 percent. Later-stage cancers have survival rates of 24 percent.

Ninety percent women who have breast cancer have no family history. “Most breast cancers are spontaneous genetic changes that occur in the individual and are not necessarily due to family history or a breast cancer gene,” says Harvey.

Myth #2: A mammogram will expose me to an unsafe level of radiation.

Fact: “While a mammogram does use radiation, it is a very small amount and is within the medical guidelines,” says Harvey. Because mammography is a screening tool, it is highly regulated by the Food and Drug Administration, Mammography Quality and Standards Act and other governing organizations, like the American College of Radiology. A mammogram is safe as long as the facility you go to is certified by the regulating agencies. There is constant background radiation in the world that we are exposed to every day. The radiation dose from a mammogram is equal to about two months of background radiation for the average woman.

Myth #3: A 3-D mammogram is the same as a traditional mammogram.

Fact: Three-dimensional mammography, or tomosynthesis, is the most modern screening and diagnostic tool available for early detection of breast cancer. Compared to a standard 2-D mammogram, a 3-D mammogram displays more images of the breast and in thin sections of breast tissue. “3-D mammograms provide us greater clarity and the ability to determine the difference between normal tissue and cancer,” says Harvey. “With 3-D mammography, the data show a 40 percent increase in detecting early cancer and a 40 percent decrease in false alarms or unnecessary recalls from screening.”

Myth #4: If I have any type of cancer in my breast tissue, a screening mammogram is guaranteed to find it. 

Fact: “While annual mammograms are very important for women, there are limitations,” says Harvey. This is mostly due to dense breast tissue — the denser the breast, the more likely it is that a cancer will be hidden by the tissue. “Normal breast tissue can both hide a cancer and mimic a cancer,” says Harvey. Other imaging methods can be used for women with dense breast tissue, such as 3-D mammographybreast MRI or breast ultrasound, to obtain additional images.

Myth #5: I had a normal mammogram last year, so I don’t need another one this year.

Fact: Mammography is detection, not prevention. “Having a normal mammogram is great news, but it does not guarantee that future mammograms will be normal,” says Harvey. “The largest trials in history have shown a 33 percent decrease in death from breast cancer in women over 40 who had regular screening mammograms.”

Myth #6: My doctor didn’t tell me I needed a mammogram, so I cannot schedule an exam.

Fact: You do not need your doctor to write you a prescription or complete an order form for you to have a screening mammogram. “The recommendation is that if you are a woman from age 40 on, you should have a mammogram every year, even if your doctor forgets to mention it,” says Harvey. Women can self-refer to make an appointment for their annual mammogram for earlier detection of breast cancer.

You May Also Like

Female doctor reviewing mammogram renderings

Mammograms and More: Breast Cancer Screening Guidelines

A Johns Hopkins expert provides screening recommendations that may lead to earlier detection, less aggressive treatment and a higher rate of survival.

Health care professional reading results to patient

Understanding Your Mammogram Report: Answers from Experts Lillie Shockney and Susan Harvey

Johns Hopkins breast imaging experts Lillie Shockney and Susan Harvey answer questions about common findings in mammogram reports.

Two women jogging on a wooded trail.

6 Heart Health Mistakes Made by Women—and How to Avoid Them

Even though you think you’re being careful, it’s still easy to slip up when it comes to keeping your heart healthy. Johns Hopkins experts give tips on how to stay on track.