Objectives: Our aim was to report a new approach of endoscopic management (endoloop and encircling suture methods) for interstitial or cornual pregnancy and to determine the safety and effectiveness of these procedures and their effects on subsequent pregnancies. Study Design: This is an uncontrolled retrospective review of 24 patients treated for interstitial pregnancies through endoscopic operations with 14 to 72 months of follow-up at a large urban medical center. Blood loss, operation time, changes of serum human chorionic gonadotropin levels, the resumption of menstruation, and subsequent pregnancy after operation were analyzed. Results: Among 24 interstitial pregnancies, 3 had ruptured at the time of operation and 21 had not ruptured. Treatment consisted of either the vasopressin and electric cauterization method, the endoloop before evacuation of the conceptus method, or the encircling suture before evacuation of the conceptus method. The blood loss and operation time (mean ± SD) for unruptured cases were 133 ± 134 mL and 51.6 ± 7.6 minutes in the vasopressin and electric cauterization group (n = 3), 32 ± 22 mL and 28.5 ± 6.4 minutes in the endoloop group (n = 15), and 40 ± 17 mL and 35.0 ± 5.0 minutes in the encircling suture group (n = 3). In 3 patients with ruptured pregnancy treated with the endoloop method, the blood loss and operation time (mean ± SD) were 1100 ± 854 mL and 82.5 ± 51.6 minutes. Any of these operative methods resulted in rapid decline of serum human chorionic gonadotropin levels within 1 week with the exception of 1 case, in which the endoloop method was used; this patient needed additional treatment with methotrexate. Seventeen patients desired pregnancy in the future, and 15 eventually became pregnant. One of these 15 pregnancies ended in an ectopic pregnancy on the opposite side 6 months after the interstitial pregnancy. Three ended in a spontaneous abortion, and 11 were delivered by elective cesarean section at term before labor started. Operative records of cesarean section in 8 patients delivered at our institution showed little or no adhesions or defect in the cornual area of the previous operation. Conclusion: The endoloop method and the encircling suture method are simple, safe, effective, and nearly bloodless. There were no uterine ruptures in the pregnancies subsequent to these methods of endoscopic management. (Am J Obstet Gynecol 2000;182:114-21.)