Suspected ectopic pregnancy: endovaginal and transvesical US.

Until the advent of endovaginal ultrasonography (US), transvesical US was the only US technique availab le for evaluation of patients with suspected ectopic gestation. A study was undertaken to assess the predictive ability of transvesical and endovaginal US and determine whether endovaginal US could be used alone. Fifty-three patients who had a positive pregnancy test finding and who were at risk for ectopic pregnancy were examined with both endovaginal and transvesical US. Twenty-nine were examined retrospectively and 24 were examined prospectively. Standard sonographic criteria were used to differentiate between intrauterine pregnancy and ectopic gestation. The clinical or pathologic diagnosis was ectopic pregnancy in 18 patients (34%), normal intrauterine pregnancy in 19 (36%), and abnormal intrauterine pregnancy in 16 (30%). Endovaginal US increased the sensitivity of detecting a live ectopic pregnancy (from 6% to 17%). Endovaginal US, by allowing early diagnosis of intrauterine pregnancy, significantly increased the diagnostic accuracy for ectopic pregnancy (from 60% to 83%). Endovaginal US provided significant additional information in women referred for sonography with a suspected ectopic gestation. On the basis of these findings it is concluded that endovaginal US can be used alone in the majority of women with suspected ectopic gestation.