A new study could reignite the debate over when women should begin routine mammograms.

Researchers at Harvard University say mammograms before age 50 could dramatically cut deaths from breast cancer.

They looked at more than 600 cases of women dying from the disease and found that 71%t never had a mammogram prior to being diagnosed. Half the deaths were women under 50.

In 2009, a government task force released a recommendation that women should get mammograms starting at age 50.

Oncologists say often the question comes down to cost. "Mammography, it's a larger number of potential people to be screened so the societal cost is greater, but the personal societal cost of breast cancer in young women is also great," said Dr. Roger Kwong from Gundersen Health System.

Meanwhile, the American Cancer Society has continued to maintain that early screening and detection saves lives. They say women should get one mammogram a year starting at age 40 while they are in good health.