Resolution of complete placenta previa: does prior cesarean delivery matter?

Objectives: The purpose of this study was to prospectively assess the rate of resolution of complete placenta previa diagnosed at second-trimester sonography in patients with and without previous cesarean delivery.

Methods: This prospective study evaluated patients at 3 institutions with complete placenta previa diagnosed at second-trimester screening sonography. All patients were followed with sonography every 4 to 6 weeks until either resolution of the previa or delivery occurred. Patients with persistent/nonresolving complete placenta previa underwent cesarean delivery.

Results: A total of 67 patients were enrolled in the study; 18 patients had a prior cesarean delivery. Resolution of placenta previa occurred in 11 of 18 patients (61%) with a prior cesarean delivery, whereas 44 of 49 patients (90%) without a prior cesarean delivery had resolution of placenta previa (P = .012, Fisher exact test). Placental location per se (anterior or posterior) was not associated with resolution of placenta previa (P = .22). Complete placenta previa persisted to delivery in 5 of 9 patients (56%) with a prior cesarean delivery and an anterior placental location.

Conclusions: This prospective study indicates that patients with a prior cesarean delivery and complete placenta previa diagnosed at second-trimester sonography are less likely to have subsequent resolution of the previa when compared to those without a history of cesarean delivery.