When a cesarean section scar is more than an innocent bystander in a subsequent pregnancy: Ultrasound to the rescue.

Over the years, cesarean section has played a pivotal role in reducing maternal and perinatal morbidity and mortality. With the rising trend of this surgery, a substantial number of pregnant women have a cesarean section scar. The scar can serve as the abode of grave conditions in subsequent pregnancies, namely cesarean scar pregnancy, morbidly adherent placenta, and scar dehiscence. Sonography has emerged as a robust tool for the diagnosis of these potentially life-threatening conditions. This review highlights the key sonographic features of various complications that can occur at the cesarean scar site in subsequent pregnancies. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45:319-327, 2017.