Utility of an algorithm to diagnose ectopic pregnancy

In recent years, algorithms have been proposed to evaluate ectopic gestations. To determine the usefulness of an algorithm for a large county hospital, a surveillance project was initiated. During 2 years, 4045 women were screened in the emergency room for pregnancy. Of these, 1648 (41%) were noted to be pregnant, initially detected by rapid enzyme immunoassay for urinary human chorionic gonadotropin, and later confirmed using quantitative radioimmunoassay for serum human chorionic gonadotropin. Within this group, 249 women were diagnosed with ectopic pregnancies. Hemoperitoneum was discovered by culdocentesis in 128 of 249 cases of ectopic gestations, all operated upon acutely. A discriminatory zone for ultrasound was diagnostic of ectopic pregnancy in only 33 cases, as the majority of women presented with human chorionic gonadotropin levels below 6500 mIU/ml. Uterine curettage performed when abnormal serial levels of chorionic gonadotropin were observed detected an additional 46 cases. Early diagnosis permitted treatment prior to tubal rupture in 147 instances with conservation of the fallopian tube in 125 (50%). We conclude: (1) even in a busy county emergency room, algorithms are useful for expediting the diagnosis of ectopic pregnancy; (2) when ectopics are diagnosed early, conservative tubal surgery is possible in many patients.