No. Dense breasts are neither unusual nor abnormal. By age:
- More than half of women under the age of 50 have dense breasts.
- About 40 percent of women in their 50s have dense breasts.
- About 25 percent of women age 60 and older have dense breasts [1, 2].
Generally, glandular tissue (which contributes to breast density) tends to shrink after menopause so that sometimes the breasts will appear less dense on mammograms as a woman gets older. However, many women continue to have dense breast tissue after menopause. During pregnancy and breastfeeding, the dense tissue grows and the breasts become denser and often larger.
The tissue composition of every breast is different (and can differ during a woman’s own lifetime) which is why women should know their own breast density and understand the limitations of mammography for their breast type.
1. Kerlikowske K, Ichikawa L, Miglioretti DL, et al. Longitudinal measurement of clinical mammographic breast density to improve estimation of breast cancer risk. J Natl Cancer Inst 2007; 99:386-395
2. Sprague BL, Gangnon RE, Burt V, et al. Prevalence of mammographically dense breasts in the United States. J Natl Cancer Inst 2014; 106