CBS News-- In one of the largest reviews to date, researchers recently looked into 50 years' worth of studies on Mammograms, and found the benefits are often over-estimated, while the harms are under-estimated.
"Mammography does have some benefit in the likelihood of dying from breast cancer, but these benefits are relatively modest and, particularly for women who are at very low risk of breast cancer, the benefits are quite small," said Dr. Nancy Keating of Brigham and Women's Hospital, Harvard Medical School.
The review estimates mammograms reduce death by about 19 percent. For women in their 40s, it's 15 percent, and for women in their 60s, it's about 32 percent.
But researchers say there are harms, such as false positives, which can lead to unnecessary biopsies and treatment.
The new research suggests women talk to their doctors about breast cancer screening, and make an individual decision based on their age and risk.
Lenox Hill Hospital's Chief of Surgical Oncology, Dr. Stephanie Bernik, says it's not just about survival. It's about finding tumors sooner so women have choices.
"You need to catch cancers early because the treatment will be easier and less involved," Dr. Bernik says.
And that's what Marie Seaquist says a mammogram did for her. Diagnosed at 43 after receiving results from her mammogram, she opted for a double mastectomy and chemotherapy.
After a year of the treatment, Seaquist says she feels great, and that she believed the mammogram saved her life.