The government is at odds with many medical experts and cancer groups over breast cancer screening after saying routine mammograms aren't necessary for women in their 40s.

The U.S. Preventive Services task force reversed its stance on existing recommendations, now saying start in your 50s, and do them every two years.

And remember those breast self-exams? Well, skip those too. The panel says there's no evidence the exams actually saves lives. So what's a woman in her 20s, 30's or 40s to think? Elisa Del Rosario would beg to differ.

"I'm a three year Breast Cancer survivor," says Del Rosario. A routine mammogram caught Elisa's breast cancer when she was just 46. She says she's concerned the change in recommendations could cost lives.

"If i had waited 'til i was 50 to get a mammogram, my breast cancer would probably be in a later stage, and i don't know what type of diagnosis i would have had."

And Elisa is not alone.

"We need to encourage women to to do all that they can and all that is within their power to do. Breast self exam being one, and annual mammograms being another at the age of 40."

At Susan G. Komen for the Cure, Executive Director Sheryl Shaw says guidelines are just that and it's important for women to take charge of their own health.

"It's very important for us not to lose sight of the fact that mammograms save lives," says Shaw, "regardless of what age breast cancer is detected, we need to save that life, whether it's at the age of 40, at the age of 30, lives are valuable."

The government task force agrees mammograms do detect cancer in women in their 40s. In fact, it says 15 percent of cancers in women that age are caught by mammograms, but it says there are downsides too.

Anne Mandelblatt from the Lombardi Cancer Center says many women end up dealing with unnecessary medical procedures and worry.

"By harms I mean there were women that would undergo false positive exams, unnecessary biopsies and even be treated for cancers that would never have harmed them."

Elisa disagrees and says she's living proof it's better to be safe than sorry.

"Fortunately, when I did get diagnosed 3 years ago, it was early enough, that i'm still here today," she says.

Breast cancer survivors who were diagnosed at a young age are among the more vocal critics of these new guidelines. The task force says this is just a recommendation, and that women should consult their own doctors about personal screening.

Breast cancer is the most common cancer and the second leading cause of cancer deaths in american women. More than 192-thousand new cases and 40-thousand deaths from the disease are expected in the U.S. this year.