Abstract
PURPOSE: To investigate the role of beta-human chorionic gonadotropin (HCG) level and its change prior to methotrexate (MTX) treatment as predictors of treatment success and to access the posttreatment observation period for ectopic tubal pregnancy. METHODS: Clinical data of 41 females treated with MTX for tubal pregnancies were reviewed and analyzed retrospectively. RESULTS: Among 41 patients, 34 achieved complete resolution without surgery. No statistically significant difference was observed in the presence of hemorrhagic ascites, serum progesterone levels, or diameters of adnexal mass between the MTX success and failure groups. Serum HCG levels on the day of MTX administration (day 1) were significantly lower in the MTX success group. Moreover, % HCG change per day, which represents the increment ratio of HCG prior to MTX treatment, was significantly lower in the MTX success group. Receiver operating characteristic (ROC) curves demonstrated that the treatment success was predicted by % HCG change per day less than +12.6% per day with a sensitivity of 87% and a specificity of 71%. The duration from treatment to complete recovery was strongly correlated with day 1 HCG levels. CONCLUSIONS: Pretreatment HCG change is a significant predictor of therapeutic success of MTX treatment, and the treatment period may be predicted from initial HCG levels.