A case report of retroperitoneal ectopic pregnancy with lymphatic migration after in vitro fertilization–embryo transfer: an explanation to embryo distant migration

Abstract

To present a rare case of retroperitoneal ectopic pregnancy with lymphatic migration after invitro fertilization-embryo transfer (IVF-ET) and propose the possible explanation for embryonic migration. Illustrative video presentation. Images, videos (educational videos), and title slides were used to introduce the case of a patient with retroperitoneal ectopic pregnancy with lymphatic migration after IVF-ET and provide a potential explanation for embryo distant migration in the patient. This work was approved by the institutional review board. University hospital. A 32-year-old woman (gravida 2, para 0) with a history of right salpingectomy was admitted to the hospital 40 days after IVF-ET because of ectopic pregnancy for 1 day; the patient had secondary infertility for 6 years. Gynecologic examination indicated anterior 40-day uterus with no tenderness. A preoperative B-mode ultrasound scan showed that the endometrium was 23 mm, and there was no acoustic image of the pregnant sac in the uterine cavity. Magnetic resonance imaging showed that 1 oval signal measuring approximately 30 × 28 × 35 mm was detected at the gap between the aorta anterior to the third lumbar vertebra and inferior vena cava. The inferior vena cava could be seen on the rear right of the gestational sac, and the abdominal aorta could be seen on the rear left. Retroperitoneal ectopic pregnancy with lymphatic migration after IVF-ET was diagnosed using B-mode ultrasound, MRI, and pathology analysis and was removed laparoscopically. Mechanism analysis of distant ectopic migration in a patient receiving IVF-ET with a history of tubal surgery. The patient was diagnosed using B-mode ultrasound and MRI and underwent laparoscopic surgery to diagnose and remove the retroperitoneal ectopic pregnancy tissue. Further, the pregnancy lesion was completely removed using an ultrasonic knife. The pathological examination showed that the pregnancy tissue was located inside an enlarged lymph node surrounded by lymphoid tissue, and lymphocyte infiltration was also seen in the endometrial tissue, suggesting that the implanted embryo migrated to the retroperitoneum through the lymphatic channels. The patient successfully conceived through IVF-ET 1 year after the operation, and a full-term neonate was delivered by cesarean section. This case reinforces that in patients with a history of tubal surgery, whether unilateral or bilateral, clinicians should pay more attention to the possibility of retroperitoneal pregnancy after IVF-ET and to the follow-up of such patients. The pathological examination report provided evidence that lymphatic migration may be the possible mechanism of retroperitoneal ectopic pregnancy or embryonic migration after intrauterine placement.