Significant increase in serum hCG levels following methotrexate therapy is associated with lower treatment success rates in ectopic pregnancy patients

Objective: To determine the association between early increase in the serum hCG levels (days 0–4) and treatment success rates following methotrexate therapy in ectopic pregnancy patients. Study design: A level II-2 case-control study of involving 140 patients treated with methotrexate for ectopic pregnancy at the gynecology department in a tertiary care hospital. Results: A logistic regression model for the “failure of treatment” was fitted with serum hCG levels change between day 0 and day 4, patient age, pregnancy age at day-0, and day-0 β-hCG level as predictors. The logistic regression analysis indicated that having more than 50% increase in the β-hCG levels between days 0 and 4 significantly (P = 0.011) increases the risk of MTX treatment failure. Conclusion: The results of this study indicate that >50% increase in β-hCG levels between days 0 and 4 significantly increases the risk of methotrexate treatment failure. This novel information could assist patients and physicians in making decisions regarding ectopic pregnancy treatment.