Ruptured primary omental pregnancy mimicking adnexal implantation

Ectopic pregnancies occur when the implantation of a fertilized ovum occurs outside of the endometrial cavity. The majority of ectopic pregnancies encountered in clinical practice are located within the fallopian tube. Abdominal pregnancies represent 1% of all ectopic pregnancies. Primary omental pregnancy, in which the extrauterine site of implantation is the greater omentum, is the least common form of abdominal pregnancy. The rarity of an ectopic pregnancy in the omentum and the absence of clinical symptoms often delays diagnosis and proper identification before rupture. The authors describe the case of a 23-year-old woman who had hemoperitoneum from a ruptured omental ectopic pregnancy that mimicked adnexal implantation. Her omental pregnancy was diagnosed through intraoperative exploration and osteopathic structural examination findings.