Placental abruption

Separation of all or part of the placenta from the wall of the uterus before the baby is delivered. The exact cause is not known, but placental abruption is more common in women with long-term hypertension and in those who have had the condition in a previous pregnancy or who have had several pregnancies. Smoking and high alcohol intake may also contribute to the risk of placental abruption. Symptoms usually occur suddenly and depend on how much of the placenta has separated from the wall of the uterus. They include slight to heavy vaginal bleeding, which can be severe haemorrhaging in complete separation; cramps in the abdomen or backache; severe, constant abdominal pain; and reduced fetal movements. If the bleeding does not stop, or if it starts again, it may be necessary to induce labour (see induction of labour). A small placental abruption is usually treated with bed-rest in hospital. In more severe cases of placental abruption, an emergency caesarean section is often necessary to save the the life of the fetus. A blood transfusion is also sometimes required.