Patient were under general anaesthesia, placed in a dorsal lithotomy position and the bladder emptied. Expose, grasp and traction the cervix. And adrenaline (600 ug/l; 10-20 ml) was injected submucosally at the level of the cervicovaginal junction. An incision was made at the anterior cervicovaginal junction, and the bladder was dissected away until the anterior peritoneal reflection was identified. The anterior drawing hook was inserted into the vaginal incision to retract the bladder upwards. The CSP was identified as a'purple bulge' located in the anterior part of the lower uterine segment. A transverse incision was made over the most prominent area of the bulge. Ectopic pregnancy tissue inside the bulge was removed, and suction curettage through the incision on the uterus isthmus was subsequently performed. The edges of the incision were trimmed with scissors, and the myometrial and vaginal defects were closed with a continuous locking suture using 2-0 absorbable sutures.

index of blood loss, haemoglobin decrease(post-operation day 2 minus pre-operation), operation time, perioperation complications,change to other treatment procedure are collected to evaluate the safety of this procedure.

serum hCG are measured every week till post-operation till it resolute to normal level. and transvaginal ultrasound are performed every month post-operation till there is no sign of any pregnancy residues.

age, gravity and parity, previous caesarean section times, interval from last caesarean section, gestation age when diagnosed, pre-treatment human chorionic gonadotropin(hCG) level and ultrasound characteristic details are collected to investigate the relation between these index and CSP