Objective: To evaluate the effect of β-hCG of treating prediction in tubal ectopic pregnancies (TEP). Materials and Methods: 758 patients receiving only one dose of methotrexate (mtx) treatment protocol for CAP were included in the study between January 2009 and December 2017. Patients' age, gravity, parity, ultrasonography findings, β-hCG values, and factors that may affect treatming process were recorded. Results: It was determined that medical treatment success was predicted with 77%, 81% sensitivity and 61% and 68% specificity when the initial β-hCG value was 1435 mIU / mL and the β-hCG level on the 4th day was 1539 mIU / mL cut off value. In our study, when β-hCG values decreased by 7% between 0-4 days were taken as cut off value, medical treatment with 84% sensitivity and 77% specificity was shown to be successful. The mean β-hCG levels on the 4th and 7th days were significantly lower in the medical treatment group than in the unsuccessful group. Conclusion: We found that patients with lower β-hCG values at baseline and day 4 had higher chances of success, and when cut off values were taken as 1435 mIU / mL and 1539 mIU / mL, success rate was significantly decreased. According to β-hCG level on day 0, day 4, and β-hCG change level between 0-4 days, we think ectopic pregnancy approach will decrease the unnecessary hospital stay.