The role of early determination of β-human chorionic gonadotropin levels in predicting the success of single-dose methotrexate treatment in ectopic pregnancy.

OBJECTIVE The aim of the study was to determine the importance of β-hCG level on day 4 following methotrexate (MTX) administration, and the difference between β-hCG levels assessed on day 0 and day 4 in predicting treatment success. MATERIAL AND METHODS A total of 68 women with tubal pregnancy, treated with a single dose of MTX, were selected for this retrospective study. RESULTS The success rate of single-dose MTX treatment in our clinic was 75% (51/68). Among 51 patients in whom MTX treatment was successful, 25 (36.8%) showed a decrease in β-hCG level of > 15% on days 0 and 4, and 44 (64.7%) showed a β-hCG level decrease of > 15% on days 4 and 7. For subjects with β-hCG decrease of > 15% on days 4 and 7, the standard error was 6.5%, and the area under the ROC curve was 81.7%, while the corresponding values for days 0 and 4 were 7.2% and 64%, respectively. CONCLUSIONS A decrease of > 15 % in β-hCG levels between days 0 and 4 does not seem to be a better predictor for success of single-dose MTX treatment for ectopic pregnancy than between days 4 and 7. A statistically significant difference was observed only in β-hCG levels on day 7 in both, successful and unsuccessful single-dose MTX groups.