As a "three-step" procedure for early diagnosis and treatment of cervical cancer, namely cytology-colposcopy-histological diagnosis, colposcopy diagnosis plays a key role as a bridge. It is still the "gold standard" for the diagnosis of cervical cancer and precancerous lesions. 1925, Hans Hinnsell, a German, invented colposcope, which developed from a hand-held magnifying glass to a photoelectric integrated colposcope widely used in clinic. Because colposcopy can enlarge the observed vulva, vagina and cervix by 65,438+00-40 times, it can observe and find smaller lesions invisible to the naked eye, localize biopsy, reduce the false negative and missed diagnosis opportunities of cytological examination, effectively improve the detection rate of positive lesions, and assist clinicians to find precancerous lesions or early cancer of lower reproductive tract as soon as possible, so colposcopy is paid more and more attention by gynecologists and pathologists. With the help of colposcopy technology, precancerous lesions or early cancers of the lower reproductive tract can be found in time, thus providing accurate and objective basis for early detection, early diagnosis and early treatment of malignant tumors of the lower reproductive tract, improving the survival rate of patients and reducing the incidence of late malignant tumors of the lower reproductive tract, especially advanced cervical cancer. 1. Abnormal clinical symptoms and signs: contact bleeding, abnormal leucorrhea, cervicitis that cannot be cured by long-term treatment; 2, clinical examination found that vulva, vagina, cervical suspicious lesions or new organisms need to be clear; 3. Abnormal cytological examination: repeated Pap smear is grade II or above, or TBS indicates LSIL or above; 4. High-risk human papillomavirus -DNA is positive, and cytological examination indicates ASCUS；; 5. Benign lesions of vulva, vagina and cervix need to be excluded before treatment; 6. Determine the lesion range before cervical conization; 7. Understand the lesion scope and vaginal involvement before operation for early cervical cancer; 8. Dynamic changes and curative effect evaluation of reproductive tract diseases during follow-up: 9. Lower reproductive tract health examination requires colposcopy. Second, the contraindications of colposcopy. Colposcopy has no absolute contraindications. Contraindications of colposcopy-guided biopsy are: 1, acute lower reproductive tract, pelvic inflammatory disease; 2. Active bleeding of lower reproductive tract; 3. Other pathological conditions that are not suitable for biopsy, such as wound repair process and severe coagulation dysfunction. Third, colposcopy examination time 1, generally after menstruation is clean; 2. Understand that cervical intraductal lesions should be performed during ovulation; 3, suspected cancer or precancerous lesions, check as soon as possible. Fourth, preparation before colposcopy 1, routine examination of leucorrhea and cervical cytology; 2. It is not suitable for sexual intercourse or vaginal medication within 3 days before examination. 3. Gynecological examination, vaginal washing or cytological sampling should not be done within 24 hours before the examination;