Naturally occurring heterotopic pregnancy in a multiparous patient: a case report.

Background: Heterotopic pregnancy, or simultaneous intrauterine and extrauterine pregnancy, occurs rarely. Consequently, clinicians might not always consider a diagnosis of heterotopic pregnancy. Transvaginal ultrasound or other imaging modalities cannot be completely relied upon to exclude heterotopic pregnancy from the differential diagnosis of pregnant patients with abdominal pain.

Case: A 32-year-old woman, G5 P3105, presented to the emergency room with acute onset of diffuse abdominal pain. Ultrasound demonstrated an approximately 8-week intrauterine pregnancy. The patient underwent exploratory laparotomy for suspected torsion of a right ovarian cyst. Repeat exploratory laparotomy was required due to symptomatic anemia. The patient underwent exploratory laparotomy and right salpingo-oophorectomy. Pathology results demonstrated a right tubal ectopic pregnancy.

Conclusion: Surgical and medical options exist for heterotopic pregnancy management. Despite negative heterotopic pregnancy results for transvaginal ultrasound, the possibility of heterotopic pregnancy should remain within the differential diagnosis of any pregnant patient with either natural or assisted reproduction technology intrauterine pregnancy who presents with abdominal pain and/or clinical signs of ectopic pregnancy.