It is normal for the postpartum dew to clear in 4-6 weeks. There are three stages of nightmare: bloody nightmare, plasma nightmare and white nightmare. The color and amount of postpartum dew change over time. Usually, if the bloody nightmare lasts for 3-4 days or more than 1 week, it is considered that the uterus is not well regenerated; if it is accompanied by abdominal pain and blood clots, it is not excluded that there is a small amount of residue or inflammation in the uterus. Plasma nightmare lasts about 10 days and then gradually turns into white nightmare. The amount of nightmare varies according to the individual condition of the mother, and it is related to the method of delivery, as well as to rest and diet after delivery. Therefore, after delivery, you should pay attention to rest, avoid straining and staying up late, maintain personal cleanliness and hygiene, and increase nutrition to promote recovery. Sexual intercourse is forbidden during the menstrual period to avoid infection. If you have prolonged malignant dew and a large amount, it is recommended to go to the obstetrics and gynecology department of the hospital for examination and treatment if necessary.