Abstract: Objective To study the early diagnosis and treatment of cesarean scar pregnancy (CSP). Methods During a 10-year period from NOV.1995 to NOV.2005,21 patients were diagnosed as CSP and treated conservatively to preserve fertility in Obstetrics and Gynecology Hospital,Fudan University.Gestational age,symptoms,methods of treatment and prognosis were retrospectively analyzed.Results The average age of the 21 women was 33(26~44).The interval from the last cesarean section was 8 months to 18 years.The average gestational age was 47 d.Among the 21 women,76.2%(16 cases)complained of vaginal bleeding and 28.6%(6 cases)experienced abdominal pain.The average period of hospitalization was 22 d(9~39 d).The Methods of treatment included systemic or local methotrexate administration,uterine artery embolization,interventional chemotherapy,hysteroscopy and lesion excision,laparotomy and excison of lesion,dilatation and curettage.Fertility was preserved for all patients. Conclusion CSP is more common than before and MTX,interventional chemotherapy and uterine artery embolization combined with curettage are effective in conservative treatment of CSP.