Despite the fact that over 50 percent of women detect their own breast masses, a review of published studies finds no benefit from breast self-exams.

Researchers reviewed two large studies of nearly 400,000 women. They found those who performed self exams had twice as many biopsies that turned out to be negative, compared to women who didn't do the exams.

Experts at The American Cancer Society say their guidelines were changed in 2003 after similar studies were released. They no longer recommend monthly breast self-exams, rather they say women should be informed of the potential risks and benefits of the test.