The value of endovaginal sonography and urinary human chorionic gonadotropin tests for differentiation between intrauterine and ectopic pregnancy.

Effectiveness of vaginal sonography combined with urinary human chorionic gonadotropin (hCG) for identification of ectopic pregnancy (EP) was studied in 107 pregnant women. Eighty-nine women had clinical symptoms suspicious of EP. It was suggested that 18 women carried an increased risk for developing EP. In 63 women endovaginal sonography showed no evidence of intrauterine pregnancy. Fifty-eight of these turned out to be pathological pregnancies. In 44 women endovaginal ultrasonography revealed intrauterine pregnancies. Thirty-two of these turned out to be viable, 10 were not viable and resulted in spontaneous abortions, and 2 turned out to be EP. The sensitivity of vaginal sonography to identify a viable intrauterine pregnancy thus was 81% and its specificity was 97%. The sensitivity and the specificity for endovaginal ultrasonography for identifying EP was 96% and 71%, respectively. Endovaginal ultrasonography demonstrated an intrauterine gestational sac in 54% of the women with urinary HCG as low as 40 IU/L to 500 IU/L. These results show that endovaginal ultrasonography is a sensitive instrument for identifying both early normal intrauterine pregnancies as well as pathological pregnancies.