Determining when to get a mammogram for the first time can be confusing for women due to conflicting messages from experts on breast cancer prevention.

The U.S. Preventive Services Task Force, an independent panel of national health experts, now recommends all women should get screened for breast cancer every other year starting at 40 and continuing through age 74. This conflicts with American Cancer Society guidelines that say women of average risk for breast cancer have the option to get a mammogram every year between 40 to 44, with a firm recommendation that women 45 to 54 get one annually. At 55, women can switch to screening every other year, the American Cancer Society says.

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Now, a study published in the Annals of Internal Medicine, suggests that a significant amount of women would wait until 50 to get screened if they knew more about the benefits and risk of mammograms. Of the 495 participants, 8% initially said they would wait until they were 50 for their first mammogram. That figure rose to 18% after they learned more about the downsides of mammograms. They include false-negative results that can give a false reassurance to women, false-positive results that lead to further imaging, possible biopsies and anxiety, and overdiagnoses – when tumors might be detected that pose no threat and would likely go unnoticed without screening.

The study highlights the importance of physicians helping women learn – and women educating themselves – about breast health, two Philadelphia breast cancer specialists said. But they were clear that the gold-standard guidelines for breast cancer screening come from the American College of Radiology and the American Society of Breast Surgeons. Those organizations recommend women with an average risk of breast cancer begin yearly screenings at age 40.

Aside from skin cancers, breast cancer is the most common cancer in women in the United States, accounting for 1 in 3 new cancers in women each year. The American Cancer Society estimates that about 310,720 new cases of invasive breast cancer will be diagnosed in women this year and about 42,250 women will die from breast cancer.

Improved 3D technology for mammograms has diminished the issue of over-diagnosis, said Dr. Alina Mateo, director of the Integrated Breast Center at Pennsylvania Hospital.

“Sometimes you do have to be called back for things that end up being nothing,” Mateo said. “But really, I think that the benefit of you catching something really outweighs the potential quote, unquote, harm.”

Dr. Chhavi Kaushik, who specializes in diagnostic radiology and breast imaging at Jefferson Health, agreed.

“You’re dealing with some anxiety, and you’re maybe going through some unnecessary tests, possibly even a biopsy,” Kaushik said. “But at the end of the day, you’re discovering in those cases that you don’t have cancer. … On one hand, we don’t want to overdo things, but on the other hand, we don’t want to be missing cancer.”

Her goal and the goal of other physicians should be to provide patients with facts “so that they can make an informed decision for themselves,” Kaushik said.

To ensure their first mammograms go smoothly, women should tell clinicians that they are new to the process, Mateo said.

“They’re going to be so nice to you and so accommodating,” she said. “All they want to do is make sure that you have as pleasant an experience as you can.”

Here are screening guidelines from the American College of Radiology and the American Society of Breast Surgeons:

• All women should have a breast cancer risk assessment by age 25.

• Women at average risk for breast cancer should start yearly mammograms at 40.

• Women at a higher-than-average risk of breast cancer should talk to their doctors about early screening, have yearly screening mammography and be offered supplemental imaging.

• Women should continue screening past age 74.

“Mounting evidence shows that Black and other minority women, (Ashkenazi) Jewish women, and others develop and die from breast cancer prior to age 50 — or even age 40 — more often than non-Hispanic white women,” The American College of Radiology said in April. “As our 2021 guidelines for average-risk women and our 2023 guidelines for high-risk women make clear, potentially giving cancer another year to advance may particularly impact these women.”

The ACR’s guidelines also state that transgender people may be at increased risk for breast cancer based on factors such as sex assigned at birth, hormone use and surgical history. Biological women transitioning to men who do not undergo mastectomies remain at their previous risk for breast cancer and should continue to be screened as such, the ACR says. Biological men transitioning to women are at increased risk compared to other men due to hormone usage and are advised to speak with their doctors about their breast cancer risk.