The uterine cavity separation proves that there is material in the uterine cavity as observed by ultrasound, whether 5mm is serious or not depends mainly on the cause of the uterine cavity separation, if the uterine cavity separation is caused by physiological reasons there is usually no need to worry, but if it is caused by pathological reasons, timely intervention and treatment is needed: I. Physiological factors When the cause of the uterine cavity separation 5mm is physiological uterine fluid caused by ovulation or menstruation and other factors, no treatment is needed and There is no harm, it is not a serious situation. Pathological factors 1, fluid in the uterus: may be caused by endometritis or cervical canal adhesions, blockage and other factors, usually healed after drug treatment, most are not serious; 2, fluid in the uterus: pathological fluid caused by pelvic inflammatory disease and physiological factors caused by fluid in the uterus, more serious, need to be combined with the patient’s symptoms to give anti-inflammatory symptomatic treatment or observation; 3, pus in the uterus: may be acute or Chronic endometritis, cervical orifice blockage or malignant tumor of the cervix, etc., which need to be dealt with in a timely manner to avoid serious consequences; 4. Residue in the uterine cavity: it may be caused by abortion or incomplete endometrial debridement, which may lead to bleeding, pelvic inflammatory disease or even more serious complications if not dealt with in a timely manner. To sum up, when the uterine cavity separation is caused by pathological factors, need to be alert, although most of the disease can be cured, but still need to do further examination to clarify the specific severity. At the same time, women should pay attention to good living and eating habits and keep their pubic area clean and hygienic.