The pedunculated type of primary peritoneal pregnancy implanted on the infundibulopelvic ligament.

BACKGROUND

Primary peritoneal pregnancy is extremely rare in the category of extrauterine pregnancy and usually has wide attachment to the peritoneal surface at the implantation site.

CASE

A 37-year-old woman had severe lower abdominal pain 13 days before laparotomy for a preoperative diagnosis of extrauterine pregnancy. The conceptus was implanted on the pedicle originating from the left infundibulopelvic ligament. A fresh embryo of approximately 6 weeks' gestation was found in the conceptus.

CONCLUSION

Primary peritoneal pregnancy may become pedunculated, and implantation on the infundibulopelvic ligament may be involved in the formation of the pedicle. A pedunculated pregnancy may increase the risk of early termination. The reflux theory may be one of the mechanisms in this case.