Placenta previa. The ultrasonographic placental localization and its influence on the mode of delivery.

Abstract In a group of 168 patients who presented with third-trimester bleeding, ultrasonographic placental localization did not provide either positive or negative false results concerning the placental site. In a group of 47 patients for whom an ultrasonographic diagnosis of placenta previa was established, an erroneous typing was done in 4 (8.5%). Of these four, one (2.1%) underwent an elective cesarean section instead of being allowed a vaginal trial of labor.