Can the Additional Dose Requirement be Determined before the Seventh Day to Successfully Treat Tubal Ectopic Pregnancy with a Single-dose Methotrexate Protocol?

Abstract

To investigate the relationship of beta-hCG changes between the first, fourth and seventh days as a predictor of the additional dose requirement in single-dose methotrexate protocol in tubal ectopic pregnancy. Observational study. Department of Obstetrics and Gynecology, Bursa Yüksek İhtisas Training and Research Hospital, between January 2017 and June 2020. Data of 123 patients with tubal ectopic pregnancy, treated with a single-dose methotrexate protocol, were retrospectively analysed. Patients who received methotrexate on the first day and achieved treatment success constituted one group. Patients who received additional doses on the seventh day and achieved treatment success, constituted the other group. Treatment success was defined as normalisation of beta-hCG levels without surgical intervention. The percentage of beta-hCG change between day-one and day-four was a significant independent variable for the additional dose treatment requirement (OR:1.07, CI:1.01-1.13, p=0.022). The cut-off value of the beta-hCG change percentage between the first and fourth day, was calculated as 4% (sensitivity 72.9%, specificity 78.9%, positive predictive value [PPV] 88.6%, negative predictive value [NPV] 56.6%). In the single-dose methotrexate protocol applied in the medical treatment of tubal ectopic pregnancy, the change in beta-hCG value between the first and fourth days may predict the need for additional doses. Administration of an additional dose of methotrexate on the fourth day may be considered, if there is less than a 4% decrease or any increase in beta-hCG value between the first and fourth days. Key Words: Ectopic pregnancy, Methotrexate, Beta human chorionic gonadotropin, Tubal pregnancy, Single-dose protocol.