Second-dose methotrexate in ectopic pregnancies: The role of beta human chorionic gonadotropin

Objective: To evaluate the role of β-hCG levels on days 1, 4, and 7 after methotrexate as predictors for second-dose requirement and success. Design: Retrospective cohort study. Setting: Tertiary university-affiliated hospital. Patient(s): A total of 1,703 patients were admitted because of ectopic pregnancy. Four hundred nine received methotrexate, of whom 73 women required a second dose. Intervention(s): The "single-dose" methotrexate protocol with 50 mg/m² was administered to patients with progressing ectopic pregnancy. Surgical intervention was performed in cases of methotrexate second-dose treatment failure. Main Outcome Measure(s): Methotrexate second-dose requirement and success according to β-hCG levels on days 1, 4 and 7. Result(s): Second-dose methotrexate was successful in 58 patients (79.4%, success group), whereas 15 patients (20.6%) failed treatment and required surgical intervention (failure group). The medians of β-hCG levels on days 1, 4, and 7 were significantly higher in the "failure group" (1,601 vs. 2,844, 2,164 vs. 3,225, and 1,915 vs. 3,745 mIU/mL, respectively). Logistic regression analysis demonstrated that day-1 β-hCG levels were the only significant independent variable for second-dose treatment outcome. The receiver operating characteristic curve for β-hCG levels on day 1 was 0.727, and at a cutoff value of 2,234 mIU/mL the sensitivity and specificity reached the optimum for treatment success (77.5% and 73.3%, respectively). Conclusion(s): Day-1 β-hCG levels were the only predictors for methotrexate second-dose requirement and treatment success. The cutoff value of β-hCG on day 1 with the optimal treatment results was found to be 2,234 mIU/mL.