Cervical cancer screening is used to find changes in the cells of the cervix that could lead to cancer. The cervix is the opening to the uterus and is located at the top of the vagina. Screening includes cervical cytology (also called the Pap test or Pap smear) and, for some women, testing for human papillomavirus (HPV). Cancer occurs when cervical cells become abnormal and, over time, grow out of control. The cancer cells invade deeper into the cervical...