First-trimester Diagnosis and Management of Pregnancies Implanted into the Lower Uterine Segment Cesarean Section Scar

Objective: To describe first-trimester ultrasound diagnosis and management of pregnancies implanted into uterine Cesarean section scars.

Methods: All women referred for an ultrasound scan because of suspected early pregnancy complications were screened for pregnancies implanted into a previous Cesarean section scar. The management of Cesarean section scar pregnancies included transvaginal surgical evacuation, medical treatment with local injection of 25 mg methotrexate into the exocelomic cavity and expectant management.

Results: Eighteen Cesarean section scar pregnancies were diagnosed in a 4-year period. The prevalence in the local population was 1 : 1800 pregnancies. Surgical treatment was used in eight women and it was successful in all cases. The respective success rates of medical treatment and expectant management were 5/7 (71%) and 1/3 (33%). Five women (28%) required blood transfusion and one woman (6%) had a hysterectomy.

Conclusions: Cesarean section scar pregnancies are more common than previously thought. When the diagnosis is made in the first trimester the prognosis is good and the risk of hysterectomy is relatively low.