The post-partum discharge is not considered completely clean until the normal amount and character of the leucorrhea is restored. Blood, necrotic membranes and other tissues are discharged from the vagina after delivery, which is known as bad dew, and most of it lasts for 4-6 weeks. After 3-4 days of delivery, the discharge is bloody and then turns into plasma discharge, which lasts for about 10 days and then turns into white discharge. The white colored discharge lasts for about 3 weeks. After delivery, the discharge turns into white or transparent color, the amount is like the usual amount of leukorrhea, there is no fishy smell and no vulvar itching, which indicates that the discharge is completely clean. If the uterus does not recover well after delivery, or if there is residue in the uterine cavity after delivery, the amount of discharge will increase, and the bloody discharge will last for a long time and be accompanied by a foul odor. When the amount, color and character of the discharge change, it is necessary to improve the examination to exclude whether there is any residue in the uterine cavity and whether there is any infection. If there is prolonged or abnormal discharge, it is important to consult a doctor for further examination to determine the cause of the disease and to provide appropriate treatment.