Basic colposcopy and technical specifications: 1. Timing of colposcopy The best time for colposcopy is within 7 to 10 days after menstrual cleansing. If necessary, colposcopy can also be performed at any time of the menstrual period, but should not be performed during the period of maximum menstrual bleeding. Vaginal intercourse, douching and medication are prohibited for 24 hours prior to colposcopy. 2. Contraindications to colposcopy There are no absolute contraindications to colposcopy. Acute lower genital tract infection or bleeding can affect the accuracy of colposcopy, therefore, colposcopy should be performed after treatment of inflammation. 3. Colposcopy procedure Colposcopy should be performed by wet dressing the cervix/vagina with 5% acetic acid solution for one minute, then examining the cervical/vaginal covered epithelium with magnification technique (5-40 times) to record the presence of cancer and precancerous lesions, and taking biopsy specimens of the suspected lesions under its guidance. For the first colposcopy in referred patients, it is recommended to use three chemicals, namely: saline, 5% acetic acid solution and compound iodine solution, in an anterior-posterior sequence for colposcopy.