E1688. Pregnancy of Unknown Location: When the Embryo Chooses its Own Destination
  1. Margaret Houser; George Washington University Hospital
  2. Nadeem Kandalaft; George Washington University Hospital
  3. Nadia Khati; George Washington University Hospital
Ectopic pregnancy (EP) is a term used to describe any pregnancy which does not implant into the uterine cavity. There are several types of EP: tubal, interstitial, ovarian, abdominal, heterotopic, cervical and implanted on a prior cesarian-section scar. Patients generally present with vague abdominal pain and vaginal spotting in the setting of a positive serum beta human chorionic gonadotropin (beta-HCG). This clinical picture prompts urgent sonographic evaluation. Accurate sonographic diagnosis is essential, as EPs can acutely rupture and are the number one cause of maternal death in the first trimester. Therefore, prompt recognition and accurate localization of an EP has significant clinical implications on patient outcomes.

Educational Goals / Teaching Points
We find that while residents can correctly identify a pregnancy as ectopic, the anatomic localization of an EP continues to be a topic of contention at times. Accurate localization and characterization are of paramount importance, as they can greatly affect clinical management. Therefore, the purpose of this pictorial essay is to discuss the different types of EPs that we encounter in our emergency department. We will review the sonographic findings, clinical pearls, management and potential complications of the varying types of EPs.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
1. To review anatomic sites of potential EP implantation. 2. To describe and illustrate sonographic findings of each type of EP and clarify how to accurately localize the site of implantation. 3. To review some imaging pitfalls and mimics of EPs. 4. To review management of each type of EP, as well as discuss potential complications.

Ectopic pregnancies can occur in varying anatomic locations. Prompt and accurate localization is of paramount importance in order to triage patients’ treatment, which may be emergent. Radiologists should know and understand the imaging findings of each type of EP in order to arrive at the accurate diagnosis and to aid clinicians in prompt and appropriate management, which ultimately leads to improved patient outcomes.