Pregnancy of Unknown Viability

  • Emily N. B. Myer
  • Jane Arrington
  • Steven L. Warsof


Bleeding in early pregnancy complicates 15 % of all conceptions and accounts for nearly 2 % of all emergency department visits. Seventy to ninety percent of these pregnancies will progress normally. The remainder will either spontaneously abort or be an ectopic pregnancy. With advances in technology, the ability to detect pregnancy at earlier gestational age, either biochemically or sonographically, provides both diagnostic assistance and challenge to practitioners. One of the more clinically challenging scenarios is the patient with a positive pregnancy test who presents with uterine bleeding or pelvic pain and whose fetus cannot be located by ultrasound. An astute clinician must always have concern for a life-threatening ectopic pregnancy or miscarriage. When the situation is uncertain, the clinician must decide if the patient has signs and symptoms highly concerning for abnormal pregnancy. This is important to avoid erroneous treatments or counseling which could not only harm a viable fetus but also may lead to significant medical legal risk. The uncertainty of diagnosis and management is especially true when physicians from multiple disciplines with different skill sets converge in the emergency department. The goal of this chapter is to clarify for the practitioner the evaluation and treatment of early pregnancy of unknown viability or location.


Early Pregnancy Ectopic Pregnancy Ovarian Hyperstimulation Syndrome Crown Rump Length Last Menstrual Period 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Beta subunit of human chorionic gonadotropin


Fetal heart rate


Fetal pole


Gestational sac


Human chorionic gonadotropin


Intrauterine pregnancy of unknown viability


Pregnancy of unknown location


Spontaneous abortion


Yolk sac


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Emily N. B. Myer
    • 1
  • Jane Arrington
    • 2
  • Steven L. Warsof
    • 1
  1. 1.Department of Obstetrics and GynecologyEastern Virginia Medical SchoolNorfolkUSA
  2. 2.Maternal Fetal MedicineEastern Virginia Medical SchoolVirginia BeachUSA

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