Nearly half of women over 40 have dense breasts, which bring an elevated risk of breast cancer and also tend to mask it in screenings.

As of Sept. 10, the U.S. Food and Drug Administration requires those getting mammogram results to also receive notice about breast density, which can help with breast cancer screenings.

The FDA will now require all mammography reports to include whether a person has breast density. Breast density is considered a risk factor for breast cancer and can make it difficult to detect signs of cancer.