Diagnosing ectopic pregnancy and current concepts in the management of pregnancy of unknown location

Hum Reprod Update. Mar-Apr 2014;20(2):250-61. doi: 10.1093/humupd/dmt047. Epub 2013 Oct 6.


Background: A diagnosis of ectopic pregnancy (EP) is primarily achieved using transvaginal ultrasonography (TVS). Pregnancy of unknown location (PUL) is the term used to categorize a pregnancy in a woman with a positive pregnancy test when no pregnancy has been visualized using TVS. This review appraises current tools for the diagnosis of EP, describes the diagnostic criteria for non-tubal EP and reviews the literature on the clinical management of PUL.

Methods: We performed a targeted search using the PubMed database. All articles published in the English language from January 1984 to March 2013 were screened for eligibility.

Results: Using TVS to diagnose EP is highly sensitive (87-99%) and specific (94-99.9%). Variations exist in the criteria used for ultrasound diagnosis. Studies report that between 5 and 42% of women seen for ultrasound assessment with a positive pregnancy test have a PUL. For PUL, measurements of serum human chorionic gonadotrophin (hCG) and progesterone are used to predict pregnancy viability and therefore give an indication of the risk of an EP. Only 6-20% of PUL are subsequently diagnosed with EP. Non-tubal EPs are relatively uncommon, difficult to diagnose and result in disproportionate morbidity and mortality.

Conclusions: Access to expertise and equipment for high-quality TVS means the majority of women with EP in developed countries can be diagnosed rapidly and accurately. Identifying PUL, which are low risk and therefore requiring less follow-up, finding better serum markers for EP and safely identifying women who do not require intervention for EP are the current diagnostic challenges.

Keywords: ectopic pregnancy; expectant management; prediction models; pregnancy of unknown location; transvaginal ultrasonography.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Biomarkers / blood
  • Diagnosis, Differential
  • Diagnostic Techniques, Surgical
  • Female
  • Humans
  • Pregnancy
  • Pregnancy, Ectopic / diagnosis*
  • Pregnancy, Ectopic / therapy
  • Risk Factors
  • Ultrasonography, Prenatal
  • Watchful Waiting


  • Biomarkers