Colposcopy involves the use of a special lighted microscope to magnify the surface of the cervix during a pelvic examination. The cervix is the lowest part of the uterus and contains the opening from the uterus to the vagina.
Who is a candidate for the procedure?
A colposcopy may be used in combination with a cervical biopsy to detect cancer of the cervix or precancerous changes known as cervical dysplasia. It is usually done after a woman has abnormal results from a Pap smear that is done as part of a pelvic examination.
A Pap smear is a test in which the healthcare professional uses a small spatula and a brush to gently scrape cells from the woman's cervix. These cells are sent to a lab for testing. The Pap smear may show early, abnormal, changes in the cells of the cervix that may lead to cancer. A woman should have a colposcopy if the following conditions apply:
- She has 2 consecutive abnormal Pap smears suggesting mildly abnormal changes
- She has had one abnormal Pap smear that suggested moderately abnormal tissue growth or more severely abnormal cells
- She has a suspicious-looking lesion on the cervix or vagina, with or without an abnormal Pap smear
- Her Pap smear suggests the presence of human papilloma virus, or HPV. This virus can cause genital warts and is linked to the development of cervical cancer.
- She has had a test done in which material swabbed from the surface of the cervix for DNA testing has found a high risk type of HPV
- She has extensive genital warts on her vulva, which are the lips at the opening of the vagina
- She was exposed to DES in her mother's uterus. Diethylstilbestrol, a potent medication to prevent miscarriages, has been associated with abnormal changes in the cervix of women exposed to DES before they were born.
How is the procedure performed?
A colposcopy is done with the woman lying on her back with her feet in stirrups. The healthcare professional places a speculum inside the woman's vagina. This instrument helps enlarge the opening of the vagina, which allows the examiner to see the cervix and vaginal interior under magnification.
To make cells more visible under the colposcope, the examiner puts a mild solution of vinegar or weak iodine on the area. If there are abnormal appearing areas, a cervical biopsy is being done at the same time as the colposcopy, the healthcare professional takes small bits of tissue, or a biopsy, from suspicious areas. The technique is called cervical punch biopsy. The woman may feel a brief pinch or cramp.
Sometimes a sample is taken from inside the cervix by scraping the cells. This is called endocervical curetting. The healthcare professional records the location of the abnormal areas and sends the tissue samples to a lab to be viewed under a microscope.