Life-threatening neutropenia following methotrexate treatment of ectopic pregnancy: A report of two cases

Abstract

Medical treatment of ectopic pregnancy with methotrexate is an increasingly common alternative to surgical management. Initial reports of methotrexate therapy described a very low incidence of complications. We report our experience with two patients who developed profound toxicity following methotrexate treatment of ectopic pregnancy. The first patient received a single dose of methotrexate (50 mg/m² intramuscularly) for a confirmed ectopic pregnancy. The second patient received three doses of methotrexate (1 mg/kg). Both patients developed life-threatening neutropenia and febrile morbidity requiring hospitalization and supportive care. To our knowledge, this is the first description of significant morbidity secondary to bone marrow suppression following methotrexate treatment of ectopic pregnancy. Most patients with ectopic pregnancy who are treated with methotrexate can expect resolution of their symptoms and a low risk of mild complications. However, serious complications after this therapy are possible and may occur even with the single-dose regimen.