The role of ultrasonography in methotrexate therapy for ectopic pregnancy

Abstract

Medical management of ectopic pregnancy with methotrexate, an antimetabolite of folic acid, is an important alternative to surgical treatment, as it ensures a similar outcome whilst being far less invasive. Ultrasound evaluation does not only facilitate an accurate diagnosis, but also helps to select patients most likely to benefit from methotrexate treatment, as opposed to those with a high likelihood of failure of medical management, who are thus eligible for primary surgical treatment. Ultrasound also allows to monitor the outcome of methotrexate therapy. This study is a review of literature regarding the management of ectopic pregnancy with methotrexate. Such ultrasound findings as the size of the ectopic mass, presence of fetal heart rate and free fluid have been confirmed as effective eligibility criteria for therapy with methotrexate. In the future, possibly also endometrial stripe thickness and the vascularity of the ectopic mass may be considered predictive of successful methotrexate therapy. The initial increase in size of the ectopic mass following methotrexate therapy confirms its effectiveness, and should not prompt concern.

Ectopic pregnancy: a resident’s guide to imaging findings and diagnostic pitfalls

“…A fetal heart rate is predictive of an advanced EP which is likely to fail IM MTX treatment. The presence of free fluid is also likely a poor predictor usually indicating rupture and surgery is more appropriate [51].…”

“…While beta-HCG is the primary way of monitoring these patients, US also serves a role. It is important to realize that an interval increase in the size of the EP is an expected sonographic finding due to hemorrhage and necrosis, and indicates treatment effectiveness [51] (Fig. 11).…”

Socioeconomic Analysis of the Surgical Management of Ectopic Pregnancies: An Analysis of the National Inpatient Sample

“…There are over 100,000 ectopic pregnancies per year in the United States, accounting for 6-13% of all pregnancy-related deaths [1,2]. Medical management via methotrexate is as cost-effective and successful as surgical treatment while avoiding the risks of anesthesia and surgery [2][3][4]. However, surgical treatment is necessary if a ruptured ectopic is suspected or if medical management via methotrexate is contraindicated [5,6].…”