What are the Risks of Having Dense Breasts?

Does having dense breast tissue affect a woman’s mammogram?⁠⁠

YES! It is like trying to see a polar bear in a snowstorm or in this case a pearl in sand! ⁠

Mammograms can be harder to read in women with dense breasts than in women with fatty breasts. ⁠
That’s because dense breast tissue and some abnormal breast changes, such as calcifications and tumors, appear as white areas in the mammogram. ⁠

As a result, mammography is less sensitive in women with dense breasts — that is, it is more likely to miss cancer. Women with dense breasts may be called back for follow-up tests more often than women with fatty breasts.⁠

Dense breasts can also put women at higher risk of interval breast cancer. This is breast cancer that is diagnosed within 12 months of a normal mammogram result. ⁠

Are dense breasts a risk factor for breast cancer?⁠

Yes, women with dense breasts have a higher risk of breast cancer than women with fatty breasts, and the risk increases with increasing breast density. ⁠

This increased risk is separate from the effect of dense breasts on the ability to read a mammogram.⁠

Should women with dense breasts have additional screening for breast cancer?⁠

In some states, mammography providers are required to inform women who have a mammogram about breast density in general or about whether they have dense breasts. ⁠

Many states now require that women with dense breasts be covered by insurance for supplemental imaging tests. ⁠

A United States map showing information about specific state legislation is available from DenseBreast-info.org

-National Cancer Institute


In Canada, great progress is being made on breast density notification. More and more women are learning if they have dense breasts, a more significant risk factor than family history. Like the USA , we’re advocating that women with dense breasts be given ultrasound in addition to mammograms. Women need to advocate for this essential screening because mammograms are not enough for women with dense breasts. ⁠

We’re very grateful to Learn Look Locate for all the awareness raising they’re doing on dense breasts & many other areas of breast health. ⁠