A Pap test (sometimes called a Pap smear) is a way to examine cells collected from the cervix, or the opening of the womb (located at the top of the vagina), for the presence of:
Precancerous changes or cancer
A Pap test, along with a pelvic exam, is an important part of a woman's routine health care because it may detect abnormalities that can lead to invasive cancer. Most cancers of the cervix can be detected early if women have Pap tests and pelvic examinations regularly. As with many types of cancer, cancer of the cervix is more likely to be successfully treated if it is detected early.
The Pap test is useful for detecting not only cancerous cells, but also other cervical and vaginal abnormalities including dysplasia (precancerous cells) and inflammation. Inflammation may be caused by:
Medications or other chemicals
A woman should always consult with her doctor about when and how often a Pap test and pelvic examination should be performed.
According to the National Cancer Institute, the American Cancer Society (ACS), and the American College of Obstetricians and Gynecologists (ACOG), general guidelines include:
Cervical cancer screening should begin at 21 years old.
The American Cancer Society (ACS) and the American College of Obstetricians and Gynecologists (ACOG) recommend cervical cytology screening with regular Pap tests every 3 years for women ages 21 to 29 years old. HPV testing should not be performed in this age group, except as a follow-up to an abnormal Pap test.
ACOG recommends that at or after age 30, women get screened with Pap tests every 3 years, or screened with a Pap test and HPV testing (co-testing) every 5 years for those that want to lengthen the interval between screenings. The ACS recommends that women at age 30 and older get tested every 5 years, adding the HPV test to the Pap test (which is preferred), or doing the Pap test alone every 3 years. However, women with certain risk factors, such as human immunodeficiency virus (HIV) infection, a weak immune system, in utero DES exposure, or a previous diagnosis of cervical cancer may need more frequent screening and should discuss this with their doctors.
Women over 65 years of age who have had regular screening (3 consecutive Pap tests or 2 consecutive co-tests) the last 10 years with normal results and are not at high risk for cervical cancer should stop cervical cancer screening, according to ACOG. Women over age 65 who have had regular screening with normal results and have no history of precancer within the last 20 years should not be screened for cervical cancer, according to the ACS.
Women who have had a total hysterectomy (removal of the uterus and cervix) do not need to undergo cervical cancer screening, unless the surgery was done as a treatment for cervical precancer or cancer. Women who have had a hysterectomy without the removal of the cervix should continue to have screening according to these general guidelines.
Women who have been vaccinated against HPV should follow the guidelines for their age group.
Women should seek expert medical advice about when they should begin screening, how often they should be screened, and when they can discontinue cervical screenings, especially if they are at higher than average risk of cervical cancer due to factors such as HIV infection or infection with the HPV virus.