Objective:To explore the incidence,risk factors and treatment for placenta accreta. Methods:A retrospective analysis was carried out from May 1997 to May 2007 in Peking Union Medical College Hospital which involved 47 placenta accreta cases and 141 controls. Results:According to our study,the incidence of placenta accreta was 0.262%(47/17,918).The percentages of placenta previa in case group were significantly higher than those of control group(P<0.01).Ninety-five point seven four percent(95.74%) of the cases were cured with conservative methods.In the second trimester,the efficiency of dilatation and curettage was 42.86%,uterine artery embolism(UAE) was 100%.In the third trimester, the efficiency of dilatation and curettage was 20.69%,tamping was 86.67%,and UAE was 100%. Conclusion:The incidence of placenta accreta in the second trimester seems increasing,which was higher than the incidence in the third trimester.The incidence of placenta accreta was only related to placenta previa.Uterine artery embolism was the best conservative management.While in the third trimester tamping was still the most effective conservative method.The majority of the cases could reserve their reproductive functions. Objective: To explore the incidence, risk factors and treatment for placenta accreta. Methods: A retrospective analysis was carried out from May 1997 to May 2007 in Peking Union Medical College Hospital which involve 47 placenta accreta cases and 141 controls. Results: According to our study, the incidence of placenta accreta was 0.262% (47 of 17,918). The percentages of placenta previa in case group were significantly higher than those of control group (P <0.01). Ninety-five point seven four percent (95.74%) of the cases were cured with conservative methods. the second trimester, the efficiency of dilatation and curettage was 42.86%, uterine artery embolism (UAE) was 100% .In the third trimester, the efficiency of dilatation and curetage was 20.69%, tamping was 86.67%, and UAE was 100%. Conclusion: The incidence of placenta accreta in the second trimester seems increasing, which was higher than the incidence in the third trimester. The incidence of placenta accreta was only related to placenta previa. Ut erine artery embolism was the best conservative management. Whilst in the third trimester tamping was still the most effective conservative method. majority majority of cases could reserve their reproductive functions.