Breast Cancer Screening Recommendations for Women at Average Risk

Mammography is the most effective breast cancer screening tool used today. However, its benefits for women vary by age. The benefits of mammography in women ages 40-49; 50-69; and 70 and older are discussed below.

Figure 3.1 shows the screening recommendations for women at average risk of breast cancer from four major health organizations.   

Breast self-exam

Breast self-exam is not recommended as a screening tool for breast cancer. Learn more about breast self-exam.   

Mammography for women ages 50-69

For women ages 50 to 69, the life-saving benefits of mammography are clear. All women ages 50 to 69 should have regular mammograms (Komen recommends every year). This guideline is based on scientific evidence from randomized controlled trials done in the United States, Canada and Europe.

A meta-analysis that combined the results from seven randomized controlled trials found women aged 50 and older who got regular mammography had a 23 percent lower risk of dying from breast cancer than their peers who did not [11]. More recent data suggest this benefit may be slightly lower. A 2010 study of women aged 50 and older who got regular mammography screening had a 10 percent lower risk of dying from breast cancer than their peers who did not get regular mammograms [17].  

Trends in screening mammography among women ages 50 to 69

Between 2000 and 2008, screening mammography rates among U.S. women ages 50 to 64 declined from 78.7 to 74.2 percent [12].

The reason(s) for this decline are unclear. However, there is concern these lower screening rates may lead to an increase in breast cancer mortality in the future.

Learn about race and ethnicity and mammography rates.  

Mammography for women ages 40-49

Mammography in women ages 40 to 49 may save lives, but the benefit for these younger women is less than for older women. A meta-analysis that combined data from eight randomized controlled trials found women 40 to 49 who had regular mammograms had a 15 percent lower risk of dying from breast cancer [18]. And, a recent study found women ages 40 to 49 who attended regular mammography screening had a 29 percent lower risk of dying from breast cancer than women who did not [19]. However, other studies have not found a benefit for women in this age group [11,18,20].

Benefits and risks of mammography for women ages 40-49

There are a few reasons why mammography may offer less benefit in younger women. Younger women tend to have dense breast tissue, which can make abnormal findings hard to see with current mammography screening [21]. Also, breast cancers in younger women tend to grow faster than breast cancers in older women [21]. This means regular mammograms every one to two years in younger women may be less likely to catch cancers early, when they are most treatable.

Compared to older women, women ages 40 to 49 have a lower risk of breast cancer. So, there are fewer benefits of screening mammography and some drawbacks, including a high rate of false positive results. A false positive result occurs when a screening test shows there is cancer when, in fact, cancer is not present. Because so few breast cancers occur in young women, those who get mammograms are more likely than older women to have a false positive result. This means they will be told they have an abnormal finding and undergo follow-up tests (such as further mammograms, ultrasounds or even biopsies) only to find they do not have breast cancer.

Learn more about follow-up of an abnormal mammogram.

Why are there differences in screening recommendations for women ages 40 to 49?

Most major health organizations, including Susan G. Komen for the Cure®, the American Cancer Society and the National Cancer Institute, feel the modest survival benefits of mammography in women ages 40 to 49 outweigh the risks of false positive results. All recommend regular mammograms for women aged 40 to 49.

However, the U.S. Preventive Services Task Force recommends routine mammography screening begin at age 50 [22]. The Task Force encourages women ages 40 to 49 to discuss the pros and cons of mammography screening with their health care providers. Then, together, they should make a decision on when to start mammography [22]. The American College of Physicians also recommends women ages 40 to 49 and their providers together make decisions about mammography [23]. Decisions should be guided by a woman's breast cancer risk profile as well as her own preferences based on the potential benefits and risks of mammography screening [23].

Read more from our Chief Scientific Advisor, Dr. Eric Winer, as he comments on the issue of mammography leading to over-diagnosis and over-treatment. 

Trends in screening mammography among women ages 40 to 49

Between 2000 and 2008, screening mammography rates among U.S. women ages 40 to 49 declined slightly (from 64.3 to 61.5 percent) [12]. The reason(s) behind this decline are unclear at this time.  

Learn about race and ethnicity and mammography rates.  

Mammography for women ages 70 and older

There are few studies on the benefits of mammography in women age 70 and older, and none of these have been randomized controlled trials. The U.S. Preventive Task Force does not recommend routine mammography screening in women ages 75 and older [22]. However, most major health organizations, including Susan G. Komen for the Cure®, recommend healthy women ages 70 and older continue to get regular mammograms [24-25]. Breast cancer risk increases with age, and mammography does not appear to be less effective for women 70 and older.  

Some women ages 70 and older stop routine screening due to poor health. Women who have a serious health problem may not benefit enough from having breast cancer found early to justify screening. However, women who are in good health and could benefit from treatment (if breast cancer were found) should continue to get mammograms. If there is any question about whether you should continue getting screened, talk to your health care provider.  

Learn about race and ethnicity and mammography rates.

Weighing the benefits and risks of mammography

Although mammography saves lives, it does have some drawbacks. Understanding your chances of having a false positive result may help lessen the anxiety over an abnormal finding on a mammogram.

The table below shows the chances of selected screening outcomes over a 10-year period for women who get yearly mammograms. In 10 years, about 2 to 6 in 1,000 women will have their lives saved by mammography; a third to a half will have at least one false positive result on a mammogram; and about a fifth will go on to have a biopsy (only a few of these women will have cancer) [26].

Learn more about weighing the risks and benefits of screening mammography and the debate over mammography.

Updated 01/23/12