The bleeding is usually as a result of poor contraction of the uterus after the birth, which fails to close off the torn blood capillaries where the placenta has pulled away. If the uterus is unable to reduce in size as it should do normally, it may be because of infection, or retention of a piece of the placenta, which later tears loose from the wall of the uterus and causes a haemorrhage. Box 3.1 summarises the common causes of late PPH.
If there is obvious excessive vaginal bleeding, or you suspect heavy bleeding may be happening internally, refer the mother urgently to the nearest hospital or to a health centre with a blood transfusion service.
Box 3.1 Causes of late postpartum haemorrhage
- Endometrial wall infection: Endometritis is described in Section 3.2.1. When the site of placental implantation (the placental bed) is not yet healed, infection in the uterus can cause the blood capillaries in the placental bed to start bleeding again.
- Poorly contracted uterus: The uterus may not contract well because of infection, retained placental fragments, or an unknown reason. As a result, bleeding can start again.
- Retained placenta: Remnants of placental tissue or fetal membranes retained in the uterus are common causes of late PPH.
- Sloughing of the placental bed: There is a possibility that the healed placental bed peels away (sloughs) and opens the blood capillaries again.
- Molar pregnancy: Although it is uncommon for a woman to develop a molar pregnancy after delivery, its occurrence can have life-threatening complications; the rapidly growing mass of grape-like tissues in the uterus can cause profuse haemorrhaging.