Use of methotrexate in the treatment of ectopic pregnancies: a retrospective single center study

The aim of this study was to evaluate the efficacy of methotrexate (MTX) in the treatment of ectopic pregnancies. We identified predictive factors of success or failure and compared our results with previous studies to make recommendations for its use.

A cohort of 61 patients from a single center was retrospectively analyzed. Inclusion criteria were a diagnosis of ectopic pregnancy and treatment with a single-dose injection of MTX. The need to perform surgery despite MTX was defined as treatment failure while needing a second MTX injection was not.

In our cohort, MTX demonstrated a success rate of 80%. This rate rose to 84% when patients with human Chorionic Gonadotropin (hCG ) > 5,000 IU/L were excluded. Twenty percent underwent surgery for pain, increased mass size and/or suboptimal hCG kinetics. Low hCG levels on days 0, 4 and 7 as well as the absence of pain, metrorrhagia and hemoperitoneum were predictive of success. MTX was also efficient in the treatment of persisting pregnancies of unknown location (PUL).

Our results are consistent with previous studies and emphasize the fact that MTX is less effective above a certain level of hCG. We obtained a cut-off value of 2439 IU/L with a sensitivity of 66.7% and a specificity of 93.9%. MTX should not be used when hCG is higher than 5,000 IU/L and laparoscopic surgery should be performed. Our results bring additional data about the efficacy of MTX in the management of persisting pregnancies of unknown location.