Aim: Methotrexate (MTX) treatment at a dose of 50 mg/m2 of body surface area (BSA) is an effective and widely used treatment method in ectopic pregnancy. However, there is a limited number of studies investigating lower MTX doses. In this study, we aimed to investigate the efficacy of lower MTX doses in the treatment of ectopic pregnancy.
Methods: This retrospective study included a total of 112 patients who were hospitalized due to ectopic pregnancy and administered single-dose MTX. The patients were divided into three groups according to the dose given as 22-40 mg/m2 of BSA (n = 17), 41-49 mg/m2 of BSA (n = 81) and ≥ 50 mg/m2 of BSA (n = 14). Data including demographic characteristics of the patients, previous history of ectopic pregnancy, previous gynecological surgeries, the use of in vitro fertilization techniques, ultrasonographic findings, beta-human chorionic gonadotropin hormone (β-hCG) levels, pre-treatment endometrial sampling, MTX doses applied, and the need for a surgical intervention during follow-up were retrieved from the hospital records.
Results: Of the patients, 16.96% (n = 19) were operated at the end of treatment, irrespective of the pre-treatment β-hCG levels with a success rate of 83% (n = 93). Fourteen (12.5%) of the patients received the second dose of MTX. The overall success rate was 89.2% in patients with a β-hCG level of ≤5000 mIU/mL.
Conclusion: This study shows that lower MTX doses than 50 mg/m2 , which has been considered standard treatment and widely used in the treatment of ectopic pregnancy for nearly three decades, are effective with similar success rates.
Keywords: ectopic pregnancy; methotrexate; single-dose; β-hCG.
© 2020 Japan Society of Obstetrics and Gynecology.