Predictive value of β-hCG decline for methotrexate success in ectopic pregnancy: A retrospective cohort with long-term fertility outcomes

INTRODUCTION: This study aimed to validate various β-hCG decline thresholds for predicting the success of single-dose methotrexate (MTX) treatment, compare fertility outcomes across different treatment modalities, and identify predictors of treatment success in women with tubal ectopic pregnancy (EP).
METHODS: This retrospective study included 687 women diagnosed with tubal EP and treated with a single-dose MTX protocol between January 2013 and May 2018. Data collected included patient demographics, clinical presentation, serial β-hCG levels, ultrasound findings, treatment modalities, and subsequent fertility outcomes. The predictive value of different percentage declines in β-hCG levels between Days 0–4 and Days 4–7 was analyzed.
RESULTS: The study included women with a mean age of 30.65±5.64 years (range: 16–53). A decline of ≥40% in β-hCG levels between Day 4 and Day 7 following MTX treatment ruled out the need for second-line intervention with 57% sensitivity and 96% specificity (AUC=0.87, 95% CI: 0.81–0.93, p<0.0001). Patients successfully treated with MTX exhibited a significantly greater mean β-hCG decline (0.39±0.24) compared with those requiring second-line intervention (0.08±0.22; p<0.0001).
DISCUSSION AND CONCLUSION: Higher β-hCG decline thresholds between Day 4 and Day 7 demonstrate high specificity for predicting successful MTX treatment in tubal EP. Tubal-preserving strategies, such as salpingostomy and MTX, appear to be associated with improved subsequent pregnancy rates compared with salpingectomy.

Keywords: Ectopic pregnancy, methotrexate, salpingectomy, salpingostomy, β, -hCG.