A new guideline has been drafted by the U.S. Preventative Task Force for women to be screened every other year for breast cancer starting at age 40.

A previous panel of experts set the precedent that women should start screening for breast cancer at age 50 and continue to get mammograms every other year after, according NPR.

NBC News reported that U.S. Preventative Services Task Force Vice Chair Dr. Wanda Nicholson said the new guidance is not for women who have a family history of breast cancer, have had previously abnormal screenings or have had their chest exposed to radiation at a young age, as they should be seen more regularly.

Though the new guideline says every other year, some doctors believe that women, no matter their health history, should be screened every year for breast cancer.

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Why did the guidelines change? Nicholson said, “With our new recommendation, it saves 20% more lives across the board for all women.”

The amount of lives saved by the new recommendations for screenings is estimated by the task force to be about 1,000 women.

The National Cancer Institute revealed that there has been a 2% increase of breast cancer among women ages 40 to 49 between the years 2015 to 2019.

Though the new guidelines say that women should be screened every other year, some doctors are saying that it should be annually, even though they are starting screenings earlier.

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Doctors think screening should happen annually: “We disagree with the U.S. task force in so many different ways,” chair of the American College of Radiology’s Breast Imaging Commission, Dr. Stamatia Destounis, said.

The American Cancer Society, along with other medical groups, already have and continue to recommend annual screenings despite the new guidelines.

The ACS detailed that its recommendations are:

  • All women should know what the mammogram screening is, what it can detect and what to expect when they go in for their screening.
  • Women ages 40 to 44 “have the option to start screening with a mammogram every year.”
  • Women ages 45 to 54 “should get mammograms every year.”
  • Women ages 55 and up “can switch to a mammogram every other year, or they can choose to continue yearly mammograms. Screening should continue as long as a woman is in good health and is expected to live at least 10 more years.”
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What has been said? “They’re taking a step in the right direction, but I do worry about the every-other year timing,” associate professor at the Yale School of Medicine Department of Radiology and Biomedical Imaging, Dr. Melissa Durand, told NBC News.

“Annual screening is going to catch the most amount of cancers when they’re at their smallest sizes and when treatment can be most effective,” Durand said. “We will miss cancers if we screen every other year.”