A condition in which the placenta is abnormally strongly attached to the wall of the uterus with superficial penetration of chorionic villi into the underlying myometrium. Women with placenta praevia and at least one previous Caesarean delivery are considered to be at high risk for placenta accreta. When placenta accreta is thought to be likely, consultant obstetric and anaesthetic input are vital in planning and conducting the delivery. Radiological input with temporary uterine balloon tamponade may be considered, and methotrexate has been used. The risk of haemorrhage, blood transfusion, and hysterectomy should be discussed. In placenta increta the chorionic villi extend into the myometrium; a placenta percreta occurs where the chorionic villi penetrate through the myometrial wall. An emergency hysterectomy is usually necessary in these rare cases.
Subjects: Medicine and Health.