Conflicting guidelines leave women unsure when to start routine mammograms

Deciding when to begin routine mammograms is confusing because major health groups recommend different starting ages-some say 40, others 45, and a recent recommendation pushes the start to 50. They also disagree on whether screening should be done yearly or every other year.

The guidelines are aimed at women at average risk and without symptoms, but defining "average" risk is difficult given how common breast cancer is. This makes it hard for individuals to weigh the benefits and drawbacks of early screening.

Dr. Laura Esserman of the University of California, San Francisco noted that breast cancer is not a single disease, so a one‑size‑fits‑all screening approach may not be appropriate. She is leading research to better identify low, high, and intermediate risk groups to eventually provide more personalized screening recommendations.

More than 320,000 women in the United States are expected to be diagnosed with breast cancer this year, according to the American Cancer Society. While death rates have been falling for decades thanks to improved treatments, breast cancer remains the second‑most common cause of cancer death among U.S. women, and new diagnoses are slowly increasing.