Bleeding again 52 days after delivery may be normal for those who are not breastfeeding, but it is not normal for those who are breastfeeding. Postpartum menstrual bleeding usually lasts 4-6 weeks and disappears completely. Menstruation may return at 6-10 weeks postpartum for those who are not breastfeeding, while for those who are breastfeeding, it may be delayed or may not return at all. When vaginal bleeding returns 52 days after delivery, it may be due to the return of menstruation, which is normal for those who are not breastfeeding, who are in good general condition and have a normal ultrasound examination. For breastfeeding patients who have vaginal bleeding 52 days after delivery, it may be due to infection, poor uterine regression, uterine residue, etc. This is abnormal and should be combined with gynecological examination, ultrasound and blood tests to assist in the diagnosis and requires active anti-infective and contraction-promoting treatments under the guidance of the doctor. Therefore, when bleeding returns 52 days after delivery, it is necessary to go to the hospital in time to find out the cause and actively deal with it.