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. Variables studied included age, gravidity, parity, previous ectopic pregnancy, serum human chorionic gonadotropin and progesterone levels, ectopic size, ectopic volume, body surface area, and yolk sac presence.

Results

Sixteen of 73 (21.9%) patients with yolk sac failed treatment vs 36 of 486 (7.4%) patients without yolk sac (P = .0003). Other significant variables on single factor analysis were previous ectopic (P = .0005), human chorionic gonadotropin (P < .0001), and progesterone (P = .003). Only previous ectopic and human chorionic gonadotropin remained significant on logistic regression analysis.

Conclusion

The presence of a yolk sac, although a risk factor for failure of single-dose methotrexate in treatment of tubal ectopic pregnancy, is not an independent predictor.

Key words: ectopic pregnancy, methotrexate, predictors of failure