Should Women Get Mammograms in their 40s?

By Charles Li MD

  • The Final Summary from the U.S. Preventative Services Task Force on Breast Cancer Screening has recommended that the decision to begin screening in your 40s should be an individual decision, weighing the harms and benefits:
  • "The decision to start screening mammography in women prior to age 50 years should be an individual one. Women who place a higher value on the potential benefit than the potential harms may choose to begin biennial screening between the ages of 40 and 49 years.
    For women who are at average risk for breast cancer, most of the benefit of mammography results from biennial screening during ages 50 to 74 years."
  • We have visualized the data behind this decision to help you decide:

Interactive Graphic Instructions: Hover over the blocks on the bottom to highlight segments, Widths are proportional to the number of patients.

Hover or tap the blocks to highlight on the graph

Out of 1000 women who undergo a mammogram in their 40s:


Of the 1000 tests will be positive results.


of the positive results will be actual cancer.


Will not have any breast cancer, a false positive result.


Will undergo an unnecessary biopsy


of false positive patients will undergo additional imaging


Case of cancer will be missed by the mammogram.

Additional Facts

Downloadable Chart (PNG) - Click to Enlarge

chart of statistics for mammograms in your 40s
More Visualizations to Explore:

Breast Self Exam Effectiveness

10 Deadliest Cancers in Women

10 Deadliest Cancers in Men

Late Stage Breast Cancer Survival


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