Cause of secondary PPH is
Causes of secondary PPH: Retained bits of cotyledon or membranes Infection and separation of slough over a deep cervicovaginal laceration Endometritis Hemorrhage from cesarean section wound Withdrawal bleeding following estrogen therapy for suppression of lactation Ref: Dutta Obs 9e pg 392.
Atonic uterus
Retained placental bits
Ruptured uterus
Cervical laceration
General obstetrics