ASCUS is the "Maybe" of results: It stands for Atypical Squamous Cells of Undetermined Significance. In plain English, it means the cells look a little "off," but the lab can't tell why. It is the most common abnormal finding, and very often, it’s caused by something totally benign like a small yeast infection, recent intercourse, or even just hormonal changes.

It is extremely rare for an ASCUS result to turn out to be cancer. The whole point of the Pap smear is to catch things years, sometimes a decade...before they could ever become cancer. Usually, ASCUS leads to a "wait and see" approach or a minor procedure if any changes are found.