Are early human chorionic gonadotropin levels after methotrexate therapy a predictor of response in ectopic pregnancy?

β-hCG level changes between days 0 and 4 after methotrexate therapy have clinical significance and predictive value. Decreasing β-hCG levels is highly predictive of treatment success. The β-hCG difference variable is a reliable predictor of success in cases with rising β-hCG levels after methotrexate therapy.