Researchers have found that mammograms are doing a good job of spotting more small cancers, but it’s not resulting in a notable decrease in the risk of dying of breast cancer.

In fact, a new study is indicating that an over-diagnosis of new cancers from all these mammograms is actually leading to harm.

Joann Elmore, a professor of medicine at the University of Washington, said in a National Public Radio report that “the more you screen, the more you are likely to detect” objects that may look like precancerous abnormalities.

Researchers came to their findings by looking at 16 million women who were at least 40 years of age and had undergone breast cancer screening in the year 2000, and found 53,207 who ended up getting diagnosed with breast cancer between initial diagnosis in 2000 until the end of 2010.

The results were unnerving: more screening turned up an 16 percent more cancers, but the breast cancer mortality rate didn’t change at all, and 25 percent more small tumors were found compared to 7 percent more large ones with increased screenings.

Some studies have shown a 20 percent reduction in breast cancer mortality with more screenings, but because mortality is fairly rare, it may not produce enough data points to track effectively. However, this new study does suggest that the early screenings are good at one thing: turning up lots of tumors with not much correlation and mortality decline.

So what’s the harm? The process of a mammogram can be quite stressful, and could be putting women through needless difficulty.

Instead, scientists may need to come up with a happy medium of the appropriate number of mammograms, which may depend on the patient.