A placental abruption or 'accidental haemorrhage', is a rare complication (about 0.5 per cent of pregnancies) that can happen if part of the placenta lifts off the wall of the uterus (usually the middle part). This can allow blood to pool and clot between the placenta and the wall of the uterus (called a retroplacental clot).
Physical signs of placental abruption
Physical signs of a placental abruption can include moderate to severe, constant abdominal or back pain (depending on the extent of the abruption), which may or may not be associated with some vaginal bleeding. Because much of the blood accumulates behind the placenta, the amount of blood coming away from the vagina may not be that much. The woman's belly is often very tender or painful to touch .
How a placental abruption is diagnosed
A placental abruption is diagnosed with an ultrasound examination, or after the placenta is delivered a large, old clot can be seen (clots can normally be seen with the delivery of the placenta but they will look fresh).
A placental abruption can be associated with health conditions such as:
Very high blood pressure. Pre-eclampsia and eclampsia are the most common causes of a placental abruption.
An injury or severe blow to the woman's stomach. This could occur in a motor vehicle accident, being kicked in the stomach or after a heavy fall.
The woman smoking or her diet being unhealthy.
A rare complication due to an external cephalic version (ECV). This is when the caregiver turns a baby from a breech position, to a head down position. Or as a rare complication from an amnioreduction. A procedure where the caregiver removes excess amniotic fluid from around the baby because of polyhydramnios.
Sometimes for no known reason.
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Last revised: Monday, 7 April 2014
This article contains general information only and is not intended to replace advice from a qualified health professional.