While it remains the second deadliest cancer among American women, the rate of breast cancer deaths has dropped dramatically—almost 40 percent—since 1989. A combination of factors including increased awareness, advances in medical treatment, and the widespread use of screening mammograms, are likely responsible for this encouraging trend.

When people get regular mammograms, the screenings help identify nearly four out of five cases of breast cancer, sometimes years before the tumor would be detectable by touch alone. Yet, despite their strong track record, regular screenings are often skipped due to misunderstandings about how they work, how much they cost, or why and when they’re needed.

“There are still a lot of misconceptions out there,” says Paula Y. Rosenblatt, MD, a medical oncologist at the University of Maryland Greenebaum Comprehensive Cancer Center in Baltimore. “But I think better breast awareness and understanding has helped the situation.”

Here are the biggest breast-screening myths, along with the facts to dispel them.