Sonographic placental localization in the determination of the site of uterine incision for placenta previa.

The presence of a placenta previa is associated with increased maternal and fetal morbidity. Hemorrhage is considered the primary underlying factor contributing to this increased morbidity. Patients who have a placenta previa are often hypovolemic and are therefore at high risk for hemorrhagic shock if intraoperative blood loss during cesarean section is not minimized. The authors reviewed sonographic localization of the placenta prior to cesarean section for placenta previa, in order to facilitate proper selection of uterine incision based on placental site and so reduce intraoperative blood loss. Nineteen cases of placenta previa were reviewed. Seventeen patients underwent a conventional low cervical or classic incision, whereas two underwent paramedian uterine incision. Data from these cases suggest that in patients who wish to be sterilized and in whom the site of placental implantation is directly beneath the lower uterine segment, as well as extending to an area in which a traditional classic cesarean section would be made, a paramedian incisional technique is of value.