To identify risk factors of peripartum complications, such as transfusion, uterine artery embolization, and Cesarean hysterectomy in women with placenta previa. 72 singleton pregnancies with placenta previa were prospectively observed for peripatum complications. In ultrasonography, the location of placenta (0:posterior, 1:others, 2: anterior), type of previa (0:partialis, 2:totalis), lacunae (0:none, 1:1–3, 2:4–6, 3:whole), placental echolucent area (0: yes, 1: no), vascularity (0:<1/3, 1:<2/3, 2:>2/3), border to bladder (0:no, 1:yes) were recorded. For clinical factors, parity (0: primi, 1: multi), history of Cesarean section (0: no, 1: yes), history of previa (0:no, 1:yes), history of abortion (0: no, 1: yes), and antepartum bleeding (0: no, 1:yes) were reviewed. Type of previa, lacunes, vascularity, history of Cesarean section or placenta previa correlated significantly with peripartum complications. However, there was no independent predictive factor for peripartum complications in multivariable analysis. When we formulated scoring system including type of previa, lacunes, vascularity, history of Cesarean section and placenta previa, all patients with total score ≥ 6 needed Cesarean hysterectomy. When total score were ≥ 4, 37.5% of patients needed uterine artery embolization or Cesarean hysterectomy. Scoring system based on ultrasonographic and clinical factors would be useful for the prediction of peripartum complications in pregnancies complicated by placenta previa.