Cutoff value of human chorionic gonadotropin in relation to the number of methotrexate cycles in the successful treatment of ectopic pregnancy

ObjectiveTo assign cutoff values for human chorionic gonadotropin (β-hCG) in pretreatment and after one methotrexate (MTX) cycle and determine its correspondence to the number of MTX cycles in successfully treated ectopic pregnancy.DesignRetrospective study.SettingPolish university hospital.Patient(s)68 women with ectopic pregnancies who qualified for medical treatment.Intervention(s)A single-dose of MTX (50 mg/m2) repeated every 7 days, plus laparoscopy in cases of tubal rupture or increased (≥50% over 1 week) β-hCG concentration.Main Outcome Measure(s)Resolution of serum β-hCG without the necessity of laparoscopy.Result(s)Success rate was 78% (53 of 64 women). The medians of pretreatment β-hCG levels in the groups treated successfully and unsuccessfully (943 vs. 3085 mIU/mL) and after the first dose of MTX (564 vs. 4049 mIU/mL) were statistically significantly different. The decrease in β-hCG level after one MTX dose differed statistically significantly only in successfully treated women. The receiver operating characteristic (ROC) curve cutoff value in the success group indicated an initial β-hCG level of 1790 and 1218 mIU/mL after one MTX cycle. The median of β-hCG titer was not statistically different in patients requiring one or more treatment cycles.Conclusion(s)When the β-hCG level is >1790 mIU/mL, the MTX treatment of ectopic pregnancy is at risk of failure. However, the initial β-hCG titer is not a predictor of the number of MTX cycles that can guarantee a successful outcome.