Diagnosis and management of ectopic pregnancy.

Ectopic pregnancy affects 1% to 2% of all pregnancies and is responsible for 9% of pregnancy-related deaths in the United States. When a pregnant patient presents with first-trimester bleeding or abdominal pain, physicians should consider ectopic pregnancy as a possible cause. The patient history, physical examination, and imaging with transvaginal ultrasonography can usually confirm the diagnosis. When ultrasonography does not clearly identify the pregnancy location, the physician must determine whether the pregnancy is intrauterine (either viable or failing) or ectopic. Use of the beta subunit of human chorionic gonadotropin (ß-hCG) discriminatory level, the ß-hCG value above which an intrauterine pregnancy should be visualized by transvaginal ultrasonography, may be helpful. Failure to visualize an intrauterine pregnancy when ß-hCG is above the discriminatory level suggests ectopic pregnancy. In addition to single measurements of ß-hCG levels, serial levels can be monitored to detect changes. ß-hCG values in approximately 99% of viable intrauterine pregnancies increase by about 50% in 48 hours. The remaining 1% of patients have a slower rate of increase; these patients may have pregnancies that are misdiagnosed as nonviable intrauterine or ectopic. After an ectopic pregnancy has been confirmed, treatment options include medical, surgical, or expectant management. For patients who are medically unstable or experiencing life-threatening hemorrhage, a surgical approach is indicated. For others, management should be based on patient preference after discussion of the risks, benefits, and monitoring requirements of all approaches.