Everything you need to know about mammograms

Breast cancer is the second most common cancer among women in the United States, and the second-leading cause of cancer death. Fortunately, regular mammograms greatly increase the chance of detecting breast cancer early, when it’s easier to treat and survival rates are highest.

When the COVID-19 pandemic began, breast cancer screening rates dropped due to stay-at-home orders and concerns about catching the virus. Mammography rates have rebounded, but they’re still nearly 15% below pre-pandemic levels.

Alison Sandberg, MD, a breast radiologist at Kaiser Permanente in Colorado, explains why it’s important to stay up to date on your mammogram.

What is a mammogram, and why do I need one?

A mammogram is an X-ray picture of the breast that is used to look for early signs of breast cancer. Regular mammograms are the best tests doctors have to find breast cancer early, sometimes up to 3 years before it can be felt in an exam.

When should I start getting mammograms, and how often should I get them?

There’s no one-size-fits-all answer. Start by having a conversation with your doctor to determine your individual breast cancer risk. Your doctor will ask you about your personal and reproductive history and the history of breast cancer in your family.

“This is especially important for women of African American or Ashkenazi Jewish descent, who may be at higher risk,” Dr. Sandberg said.

At Kaiser Permanente, women with average breast cancer risk have the option of beginning annual mammograms anytime in their 40s. For women with above-average risk, recommended screening schedules vary. Talk to your doctor about your specific situation.

For women ages 50 to 75 with average breast cancer risk, Kaiser Permanente recommends mammograms every 1 to 2 years. Women 75 and up should talk with their physician about the benefits and risks of continued screening.

Are mammograms safe?

Each time you get a mammogram, you are briefly exposed to a very small amount of radiation, but the benefits of mammography outweigh any possible harm from the radiation exposure. In fact, the dose of radiation used for a mammogram of both breasts is roughly equal to the background radiation you’re exposed to just by living in the United States for 7 weeks.

What does it mean to have dense breasts?

All breasts contain glandular, connective, and fatty tissue. Dense breasts have higher amounts of glandular and connective tissue and lower amounts of fatty tissue. Nearly half of all women 40 and older have dense breasts. But only a mammogram can show if a woman has dense breasts — it can’t be felt in an exam.

Women with dense breasts have a higher chance of getting breast cancer. Dense breasts can also make it harder for doctors to evaluate mammogram results because fibrous and glandular tissue can look similar to a tumor. Getting regular mammograms allows your doctor to see small changes in your breasts over time.

Does mammography screening work?

Yes. Mammography has helped reduce breast cancer mortality in the U.S. by nearly 40% since 1990.

“What we're doing is saving lives,” said Dr. Sandberg.

Learn more about cancer care at Kaiser Permanente.