A false positive on a mammogram can lead to anxiety, financial fallout, and time sacrificed for follow-up appointments. A new study finds they may also lead women to avoid going back for future screenings.

Research recently published in the journal Annals of Internal Medicine investigated how false positives impact subsequent mammogram scheduling. After looking at data from 177 different health care facilities between 2005 and 2017, the study showed that, compared with patients who had received true negative results, patients who got false positives were less apt to return for their next screening. This was especially true if they were asked to have a follow-up mammogram in six months or they had two false positives in a row. This is concerning to researchers due to the importance of mammograms in catching breast cancer early, when it’s more treatable.

Diana Miglioretti, the study’s lead author and researcher at UC Davis Comprehensive Cancer Center, explains, “The finding raises concerns about the potential unintended consequence of false positive results, where women may avoid screening mammograms in the future.”

To see how often future mammograms were avoided, Miglioretti and her team looked at the outcomes of more than 3.5 million mammograms performed in just over a million women aged 40 to 73. About 10% of the screenings yielded false positives. The team then looked into whether or not the patients returned for a screening within nine to 30 months after a false positive versus a true negative.

The study showed that 77% of patients with true negatives returned for their next appointment, compared with 67% who’d had a false negative and biopsy and 61% who’d had a false negative and been asked to come back for another mammogram in six months. Additionally, only 56% of women who’d had two false positives in a row came back for their next screening. These lower rates occurred regardless of the results of their prior mammograms within the past five years.

The team also found that Asian and Hispanic/Latina women had the largest reduction in likelihood of returning.

The researchers say their findings raise concerns about whether women will continue screening after a false positive. They also underscore the need for doctors to explain false positives to their patients, along with the importance of mammograms.

Miglioretti says, “It is important for women with false-positive results to continue screening every one to two years. Having a false positive result, especially if it results in a diagnosis of benign breast disease, is associated with an increased risk of being diagnosed with breast cancer in the future.”

According to the American Cancer Society, about half of women screened annually over a period of 10 years will experience at least one false positive. This is more common on a first mammogram, in younger patients, and in those with dense breasts, who have had biopsies, who have a family history of breast cancer, or who are taking estrogen. This can be due to breast density making it difficult to read images, calcium deposits, overlapping tissue causing suspicious-looking images, or normal breast tissue variations that can also look suspicious.