Hysteroscopic diagnostic techniques are increasingly used in the field of obstetrics and gynecology because they are intuitive and nearly non-invasive, but they are still unfamiliar to many patients, who are afraid because they do not know. Today to explain, may you walk into our consultation room with ease. It is this mouth that keeps the baby safely inside during the process of conception, without this tightly tied mouth, many things would have happened. It is also the mouth that causes some pain during the hysteroscopy, but it is bearable. An optical test tube, no thicker than a pencil, is inserted through the vaginal cervix into the uterine cavity, and a camera is attached to it to reproduce the image of the uterine cavity on a monitor for the doctor to observe and record, and for you to see. During the exam I will tell you, “Take a look at your uterine cavity, it doesn’t happen very often.” Of course there are some patients who experience some pain due to the narrow, hard cervical canal and hyperflexion of the uterus, but most can tolerate it and most exams are very short, so there is no need to be overly nervous. Of course, if you are highly sensitive to pain and are psychologically fragile, we can provide painless techniques, i.e. short-acting intravenous anesthesia, and everything is OK after a good night’s sleep. The most common indication for hysteroscopy in gynecology is abnormal bleeding, and most patients come to find out “where is the bleeding”, which requires a clear field of view for hysteroscopy, and bleeding will affect the effect of microscopic observation. Therefore, most doctors do not want to examine you during heavy bleeding and you have been bleeding for a long time, so it is recommended to examine you when the bleeding has decreased. Another common indication for hysteroscopy is abnormal echogenicity of the uterine cavity suggested by ultrasound. In these patients, we ask you to keep your bladder somewhat full and to combine ultrasound during the procedure to improve accuracy. For example, in uterine fibroids, abnormal uterine development, endometrial polyps, etc., the image formed after the uterine cavity is filled with puffy fluid is clearer under ultrasound. In addition, a moderately filled bladder can correct an overly anteflexed uterus and reduce pain during the examination, so please cooperate. It is useful for proximal obstruction of the fallopian tubes where the mucosa has not been destroyed, but it is not invincible and can sometimes be disappointing.