Clinical predictors of failing one dose of methotrexate for ectopic pregnancy after in vitro fertilization

Use of Methotrexate in Gynecologic and Obstetric Practice: What the Radiologist Needs to Know

Methotrexate (MTX) is the primary pharmaceutical agent that is used for management of disorders arising from trophoblastic tissue. Its widespread international use is mostly attributable to its noninvasive, safe, and effective characteristics as a treatment option for ectopic pregnancy (EP) and gestational trophoblastic disease (GTD), with the large added benefit of fertility preservation. Although the effects of MTX usage are well documented in the gynecologic and obstetric literature, there is a scarcity of radiologic literature on the subject. Depending on the type of EP, the route of MTX administration and dosage may vary. US plays an essential role in the diagnosis and differentiation of various types of EPs, pregnancy-related complications, and complications related to MTX therapy, as well as the assessment of eligibility criteria for MTX usage. A knowledge of expected imaging findings following MTX treatment, including variability in echogenicity and shape of the EP, size fluctuations, changes in vascularity and gestational sac content, and the extent of hemoperitoneum, is essential for appropriate patient management and avoidance of unnecessary invasive procedures. A recognition of sonographic findings associated with pregnancy progression and complications such as tubal or uterine rupture, severe hemorrhage, septic abortion, and development of arteriovenous communications ensures prompt patient surgical management. The authors discuss the use of MTX in the treatment of disorders arising from trophoblastic tissue (namely EP and GTD), its mechanism of action, its route of administration, and various treatment regimens. The authors also provide a focused discussion of the role of US in the detection and diagnosis of EP and GTD, the assessment of the eligibility criteria for MTX use, and the identification of the sonographic findings seen following MTX treatment, with specific emphasis on imaging findings associated with MTX treatment success and failure. Online supplemental material is available for this article. ^©RSNA, 2021.

Conservative treatment in non-tubal ectopic pregnancy and predictors of treatment failure

OBJECTIVES

To find possible predictive factors to predict the failure of conservative treatment of non-tubal ectopic pregnancy. For that purpose, we assessed the rate of failure, complications and need for additional interventions of the different primary treatment regimens in non-tubal ectopic pregnancies that occurred in our center.

STUDY DESIGN

Retrospective single-center study conducted at Hospital Clínic of Barcelona (Spain). Conservative treatment regimens included medical (systemic single or multiple dose methotrexate; ultrasound-guided intrasaccular injection of methotrexate or chloride potassium; surgical (oophorectomy in case of ovarian ectopic pregnancy, surgical curettage). The main outcome measures were success of primary treatment and the need for additional interventions. The secondary outcomes were success rate of conservative treatment, incidence of complications, days to discharge from the hospital, days until negative β-hCG, days until complete resolution of the process. Possible predictor factors for primary treatment failure were assessed.

RESULTS

A total of 39 cases were included. Primary treatment was successful in 74 % (29/39). The rate of failure of primary treatment was higher in the group with presence of embryo heartbeat than in the group without, 46 % vs. 15 % respectively (p < 0.0001). Among the cases that required additional treatments, none of them required hysterectomy. Presence of embryo heartbeat significantly increased the likelihood of failure of the primary treatment (OR 4.71, 95 % CI 1.03-21.65, p < 0.05). Every doubling of the β-hCG levels increased the risk of treatment failure by 54 % (OR 1.54, 95 % CI 1.03-2.39, p < 0.05).

CONCLUSIONS

Conservative treatment is a safe option for treatment of non-tubal ectopic pregnancy. The presence of embryo heartbeat and β-hCG levels at diagnosis may be used as predictive factors of failure of conservative treatment.