Abnormal pap smear results lead to D&C exams primarily in cases in which the pap test does not indicate the place from which the abnormalities originate, according to ehealthMD. Physicians use tissue collected from D&C exams to locate the abnormal cells.
Pap smears identify cervical cancer and precancerous cervical conditions in approximately 95 percent of cases, notes ehealthMD. However, in certain cases, the pap smear test is unable to indicate whether abnormal cells originated from the cervix or the lining of the uterus. During the D&C procedure, physicians enlarge the cervix and scrape tissue from inside the uterus and cervical canal, which is then examined.