The American Cancer Society recommends a woman should be 21 years old at the time of first cervical cancer screening. Follow-up cancer screening should occur every 2-3 years. In women younger than age 21, screening with the Papanicolaou (Pap) test may show changes in cervical cells that may be mistaken for cancer. This could lead to unnecessary secondary testing. Women below the age of 21 have a very low risk of cervical cancer, so waiting until age 21 is considered an acceptable risk.