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 to 49; 50 to 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 [14,18-20,60]. Learn about screening recommendations for women at higher risk of breast cancer.   

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 to 69

Figure 3.1 shows the screening recommendations for women at average risk of breast cancer.

For women ages 50 to 69, the life-saving benefits of mammography are clear. All women ages 50 to 69 should have mammograms on a regular basis. 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 regularly got mammograms 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 screening mammograms had a 10 percent lower risk of dying from breast cancer than their peers who did not get regular mammograms [21]. 

Trends in screening mammography among women ages 50 to 69

Between 2000 and 2010, screening mammography rates among U.S. women ages 50 to 64 declined from about 79 to 73 percent [14].

The reason(s) for this decline are unclear. Whether this decline will result in increased breast cancer mortality (death) is not known.

Learn about disparities in screening mammography.  

Mammography for women ages 40 to 49

Figure 3.1 shows the screening recommendations for women at average risk of breast cancer.

Mammography in women ages 40 to 49 may save lives, but the benefit for 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 mammograms on a regular basis had a 15 percent lower risk of dying from breast cancer [22]. And, a recent study found women ages 40 to 49 who got mammography screening on a regular basis had a 29 percent lower risk of dying from breast cancer than women who did not [23].

However, other studies (including nine randomized controlled trials and a meta-analysis) have shown mammography screening in women ages 40 to 49 does not lower the risk of dying from breast cancer [11,24].

Benefits and risks of mammography for women ages 40 to 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 technology [25]. Also, breast cancers in younger women tend to grow faster than breast cancers in older women [25]. This means having a mammogram 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 have concluded that the modest survival benefits of mammography in women ages 40 to 49 outweigh the risks of false positive results and recommend regular mammograms for women aged 40 to 49 [18].

However, the U.S. Preventive Services Task Force recommends routine mammography screening begin at age 50 [19]. 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 [19]. The American College of Physicians also recommends women ages 40 to 49 and their providers together make decisions about mammography [26]. These decisions should be guided by a woman's breast cancer risk profile as well as her own preferences based on the potential pros and cons of mammography screening [26].

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 2010, screening mammography rates among U.S. women ages 40 to 49 declined slightly (from about 64 to 62 percent) [14]. The reason(s) behind this decline are unclear at this time.

Learn about disparities in screening mammography.  

Mammography for women ages 70 and older

Figure 3.1 shows the screening recommendations for women at average risk of breast cancer.

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 [19]. However, many major health organizations recommend healthy women ages 70 and older continue to get mammograms on a regular basis [18,27]. 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 regular 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 disparities in screening mammography. 

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 some screening outcomes over a 10-year period for women who get yearly mammograms. In 10 years, between 2 and 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) [28].

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

Updated 05/20/13