Readmission following methotrexate treatment for tubal pregnancy.

OBJECTIVE: To identify risk factors for readmission following methotrexate treatment for tubal pregnancy.

METHODS: A retrospective study undertaken in two tertiary medical centers, including all individuals with medically treated tubal pregnancy (N = 511), between December 2009 and June 2021. Individuals with and without readmission following methotrexate treatment were compared. The primary outcome was the readmission rate. Secondary outcomes included the rate of post-discharge gynecological emergency department visits, tubal rupture rate, and the eventual need for surgical treatment.

RESULTS: Readmission following methotrexate treatment occurred in 224/511 patients (43.8%). Most readmissions were due to abdominal pain or suspicion of treatment failure. Readmitted individuals were more likely to have a history of pelvic inflammatory disease and pretreatment serum human chorionic gonadotropin (hCG) >2000 mIU/mL. Both factors remained significantly associated with higher readmission rates in a logistic regression analysis (adjusted odds ratio [OR] 6.28, 95% confidence interval [CI] 1.30-30.45, and adjusted OR 2.73, 95% CI 1.83-4.07, respectively) after adjustment for age, endometriosis, tubal pathology, abdominal pain, and presence of yolk sac or embryo at diagnosis. A dose-dependent association was observed between pretreatment serum hCG levels and readmission rate (P < 0.001). Pretreatment hCG levels were also associated with tubal rupture and the eventual need for surgical treatment (P < 0.001 for both). A prediction model using hCG was not sufficiently accurate to predict readmission risk.

CONCLUSION: Readmission following methotrexate treatment for tubal pregnancy was independently associated with previous pelvic inflammatory disease and pretreatment serum hCG levels. The latter was also associated with surgical intervention rate.