title: Resolution of complete placenta previa: does prior cesarean delivery matter?
abstract: OBJECTIVE
  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.
authors.affiliation: Department of Obstetrics and Gynecology, Mayo Clinic College of Medicine, 200 First St SW, Rochester, MN 55905, USA.
authors.forename: Ann K
authors.initials: AK
authors.lastname: Lal
authors.forename: Jessica
authors.initials: J
authors.lastname: Nyholm
authors.forename: Joseph
authors.initials: J
authors.lastname: Wax
authors.forename: Carl H
authors.initials: CH
authors.lastname: Rose
authors.forename: William J
authors.initials: WJ
authors.lastname: Watson
mesh_terms: D000328:Adult; D017604:Cesarean Section, Repeat / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008875:Middle Aged; D008910:Minnesota / Q000453:epidemiology; D010923:Placenta Previa / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D015995:Prevalence; D018570:Risk Assessment; D012307:Risk Factors; D016216:Ultrasonography, Prenatal / Q000706:statistics & numerical data*; D055815:Young Adult