Those with suspicious medical history, such as contact bleeding, irregular vaginal bleeding, excessive leucorrhea without obvious cause, leucorrhea with blood and no abnormal cytology; positive or suspicious cytology, Pap grade IIb or above, LCT, TCT suggesting ASCUS/ASC-H/ASGUS/LSIL/HSIL negative cytology, but suspicious by the doctor’s visual observation, such as cervical mass, cervical epithelium large missing area, cervical bleeding prone, leukoplakia or family with cervical cancer; benign cervical lesions to rule out cancer before treatment; cervical precancerous lesions and early cancer to know the extent of lesions before surgery; lower genital tract warts; HPV 16 and/or 18 positive; follow-up after treatment for cervical cancer and precancerous lesions; vulvar and vaginal lesions. Precautions before colposcopy: do not use vaginal suppositories and stop sexual intercourse within 2 days before the examination; no vaginal operations such as gynecological examination within 24 hours before the examination; no examination during the inflammatory period; no examination within 1 week before menstruation; those with abnormal coagulation function should be examined after treatment.