Pregnancy of Unknown Viability
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.
KeywordsObesity Methotrexate Progesterone
Beta subunit of human chorionic gonadotropin
Fetal heart rate
Human chorionic gonadotropin
Intrauterine pregnancy of unknown viability
Pregnancy of unknown location
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