Yolk sac on transvaginal ultrasound as a prognostic indicator in the treatment of ectopic pregnancy with single-dose methotrexate.

Objective: To determine whether yolk sac on transvaginal ultrasound was an independent predictor for single-dose methotrexate failure for tubal ectopic pregnancies.

Study Design: Seven hundred sixty-six consecutive methotrexate-treated ectopic pregnancy patients were reviewed. After excluding 25 oral and 97 multidose methotrexate patients, 18 cornual, 4 cervical pregnancies, and 63 patients with ectopic cardiac activity, 559 study patients remained.