Pelvic ultrasound performed by emergency physicians for the detection of ectopic pregnancy in complicated first-trimester pregnancies

Ann Emerg Med. 1997 Mar;29(3):338-47. doi: 10.1016/s0196-0644(97)70345-7.


Study objective: To determine the accuracy and application of pelvic ultrasound performed by emergency physicians in detecting ectopic pregnancy (EP) in complicated first-trimester pregnancies.

Methods: We studied consecutive pelvic ultrasounds performed in all women who presented with abdominal pain or vaginal bleeding during the first trimester of pregnancy over a 6-month period. Patients with clinical evidence of incomplete abortion were not included. We compared ultrasound results with subsequent ultrasound findings by the radiology department and correlated them with follow-up diagnoses and outcomes.

Results: Of the 136 eligible patients, a final diagnosis was rendered in 125; 11 were lost to follow-up. These ED ultrasound findings were recorded: established intrauterine pregnancy (IUP) with embryonic structures, 87 (70%); indeterminate scan revealing no distinct evidence of IUP or EP, 15 (12%); early intrauterine gestational sac of less than 6 weeks without embryonic structures, 12 (10%); EP, 8 (6%); blighted ovum, 2 (2%); and molar pregnancy, 1 (1%). The initial ED ultrasound determination was consistent with radiology department findings, final outcome, or both in 121 (96%) (95% confidence interval [CI], 91% to 97%). ED ultrasound accurately identified 87 pregnancies with intrauterine embryonic structures, including 5 patients with fetal demise (95% Cl, 97% to 100%). Diagnosis of pregnancy location in these 87 patients effectively ruled out EP, with a negative predictive value of 100%. The sensitivity and specificity of ED ultrasound in the detection of EP were 90% and 88%, respectively.

Conclusion: Pelvic ultrasonography performed by emergency physicians can be used to rule out EP and make an accurate diagnosis in most patients with complicated first-trimester pregnancies during the initial ED visit. The remaining patients at risk can be identified and a diagnosis made by means of follow-up ultrasound and serial hCG determinations.

MeSH terms

  • Adult
  • Chorionic Gonadotropin / blood
  • Confidence Intervals
  • Female
  • Fetal Death / diagnostic imaging
  • Gestational Age
  • Humans
  • Predictive Value of Tests
  • Pregnancy
  • Pregnancy Complications / diagnostic imaging*
  • Pregnancy Trimester, First
  • Pregnancy, Ectopic / diagnostic imaging*
  • Prospective Studies
  • Sensitivity and Specificity
  • Ultrasonography


  • Chorionic Gonadotropin