••• Chapter 19^ The Placenta and Umbilical Cord^201
❍ What are the complications of placenta previa?
Longer hospital stay, cesarean delivery, abruptio placenta, postpartum hemorrhage, fetal malpresentation,
disseminated intravascular coagulation (DIC), maternal death.
❍ What is placenta accreta?
Trophoblastic invasion beyond the normal boundary established by Nitabuch layer.
❍ What is placenta increta?
Placental invasion extends into the myometrium.
❍ What is placenta percreta?
Placental invasion beyond the uterine serosa.
❍ What are the risk factors associated with placenta accreta?
Placenta previa, prior uterine surgery, advanced maternal age, multiparity, Asherman syndrome, submucous
leiomyoma, and anterior placenta.
❍ What is the frequency of placenta accreta?
1 in 2500 deliveries.
❍ What is the risk of placenta accreta for placenta previa with no history of prior cesarean delivery?
4% to 6%.
❍ What is the risk of placenta accreta for placenta previa and one prior cesarean delivery?
10% to 25%.
❍ What is the risk of placenta accreta for placenta previa and two or more prior cesarean deliveries?
50%.
❍ What are the methods of diagnosing placenta accreta prior to delivery?
Ultrasound and MRI.
❍ What gray-scale ultrasound findings have been associated with placenta accreta?
Placental lacunae (lakes).
Loss of the retroplacental clear zone.
Uterine serosa-bladder line interruption.
❍ What is the standard of care treatment for placental accreta?
Hysterectomy after delivery.