Placental abruption is defined as separation of the placenta from the decidua basalis before delivery of the fetus. Bleeding occurs from the exposed decidual vessels, and may be extensive. However, because haemorrhage is often occult – with blood collecting around the placenta and fetus or in the myometrium and broad ligaments, the amount of blood lost is easily underestimated. Fetal distress occurs because of loss of area for maternal-fetal gas exchange. Abruption is an important cause of intrauterine growth retardation, premature labour and fetal death.
Anne Sophie Ducloy and Juliette Lee