Methotrexate for CSPs.

Expectant management of a cesarean scar pregnancy (CSP) is associated with a high risk of severe maternal morbidity. Therefore, most experts recommend immediate termination after the diagnosis of a CSP. However, there is no consensus about the optimal management of a CSP in terms of efficacy, safety, and preservation of future fertility. Methotrexate (MTX) is a folic acid antagonist that has been largely used to treat tubal ectopic pregnancies. This review summarizes the current knowledge and uncertainties about the administration of MTX as a medical or non-invasive option to terminate a CSP; the preferred injection route (systemic or local/intragestational), the comparison with other treatment modalities, and the prognostic factors for MTX success will be discussed, as well as the recommendations from scientific societies.