A Pap smear is a safe way to screen for cervical cancer. However, a Pap smear isn't foolproof. It's possible to receive false-negative results — meaning that the test indicates no abnormality, even though you do have abnormal cells.

A false-negative result doesn't mean that a mistake was made. Factors that can cause a false-negative result include:

  • An inadequate collection of cells
  • A small number of abnormal cells
  • Blood or inflammatory cells obscuring the abnormal cells

Although it's possible for abnormal cells to go undetected, time is on your side. Cervical cancer takes several years to develop. And if one test doesn't detect the abnormal cells, the next test most likely will.

Oct. 31, 2012