Placental abruption Health Dictionary

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

A small placental abruption is usu-tal. In more severe

ergency caesarean section is often necessary to save the the life of the fetus. A blood transfusion required.

placenta praevia Implantation of the placenta in the lower part of the uterus, near or over the cervix. Placenta praevia occurs in about 1 in 200 pregnancies. It varies in severity from marginal placenta praevia, when the placenta reaches the edge of the cervical opening, to complete placental praevia, when the entire opening of the cervix is covered. Mild placenta praevia may have no adverse effect. More severe cases often cause painless vaginal bleeding in late pregnancy. If the bleeding is slight and the pregnancy still has several weeks to run, bed rest in hospital may be all that is necessary. The baby will probably be delivered by caesarean section at the 38th week. If the bleeding is heavy or if the pregnancy is near term, an immediate delivery is carried out. placenta, tumours of See choriocarcinoma; hydatidiform mole.

see abruptio placentae.