If bright red blood appears again after 12 days of clean dew, it may be caused by improper diet, poor uterine rejuvenation, uterine cavity residue, puerperal infection, etc. The mother can go to the hospital gynecology department in time for ultrasound examination to clarify the cause and treat the cause. Common causes and treatment methods 1, improper diet: the mother in the postpartum excessive tonic, such as eating too much ginseng, deer antler, red dates, gum, etc., can appear after the dew clean and bright red blood. Women in the postpartum period should pay attention to avoid excessive supplementation, it is appropriate to eat a light diet rich in high-quality protein, nutritious and easy to digest; 2, poor uterine regeneration: whether it is a normal birth or a cesarean section, the uterus usually needs to return to the normal state of non-pregnancy in 5-6 weeks after delivery. And 12 days after delivery, the uterus is still in the repair stage, so the phenomenon of bright red blood may appear again after the malodex is clean. Breastfeeding women can promote contraction and repair of the uterus by breastfeeding regularly. Non-breast-feeding women or those with more bright red blood can take new biochemical pellets under the guidance of a doctor; 3. Uterine cavity residues: If there are still residues in the uterine cavity after childbirth, placenta residues or blood clot residues, the mother may have bright red blood after the dew is clean. This can be treated symptomatically based on ultrasound results. If there is a small amount of blood clot residue, oral treatment with medicines such as motherwort granules and new biochemical granules can be given. If there is residual placental tissue, surgical treatment of uterus removal is required. 4. puerperal infection: manifested as inflammation of vulva, vagina and cervix, such as uterine inflammation, peritonitis, etc. In serious cases, it may lead to sepsis and sepsis, which may show fever, pain, abnormal malignant dew, increased discharge, etc. Apply broad-spectrum high-efficiency antibiotics, such as penicillin antibiotics for anti-infection treatment under the guidance of a doctor. If necessary, bacterial culture and drug sensitivity tests can be conducted to apply the appropriate effective antibiotics; 5. Other: If the mother has a combination of cervical orifice lacerations, cervical polyps, cervical erosion, cervical cancer, etc., which can also lead to such phenomena, it is recommended to go to the hospital in a timely manner for symptomatic treatment.