Risk factors and human chorionic gonadotropin trends in patients with ruptured tubal ectopic pregnancies despite methotrexate treatment

Study Objective: To investigate the risk factors and human chorionic gonadotropin (hCG) trends in patients with ruptured tubal ectopic pregnancies (EPs) despite methotrexate (MTX) treatment. Design: Case-control study. Setting: Academic center. Patients: Patients receiving MTX for sonographically-confirmed tubal EPs after IVF between 2004-2014. Baseline demographics and hCG trends of patients with EP rupture after MTX (cases) were compared to patients with resolved EPs after MTX (controls). Intervention: Intramuscular MTX. Measurements and Main Results: Baseline demographics recorded were age, body mass index (BMI), parity, smoking status, presenting symptoms, and gestational age at diagnosis. hCG levels were measured on the day of MTX, as well as day-4 and day-7 after MTX. Odds ratios (OR) with 95% confidence intervals (CI) for EP rupture vs. EP resolution were estimated. 137 patients were diagnosed with EPs during the study duration: 27 cases and 110 controls. There was no difference in the baseline demographics of the two groups; however, patients with ruptured EPs after MTX were more likely to have vaginal spotting (OR 3.19; 95% CI 1.3-7.7) compared to those with resolved EPs. There was no difference in hCG levels on the day of MTX (1285.6 ± 233.6 vs. 1326.6 ± 307.3 IU/mL) between cases and controls. However, patients with ruptured EPs after MTX had higher hCG levels on day-4 (1223.9 ± 243.5 vs. 1111.2 ± 179.7 IU/mL; P < 0.001) and day-7 (1156.9 ± 206.2 vs. 872.4 ± 690.2 IU/mL; P < 0.001). (Table presented) Data represented as mean (standard deviation). The odds of EP rupture compared to EP resolution were 6.2 (95% CI 2.1-19.1), 13.7 (95% CI 4.84-38.9), and 3.0 (95% CI 1.2-7.2) times higher when the change in hCG levels was <5% between day-7 vs. day of MTX, day-7 vs. day-4, and day-4 vs. day of MTX, respectively. Conclusion: Patient with ruptured tubal EPs despite MTX present more frequently with vaginal spotting and have <5% change in hCG levels between the day of MTX and day-4 or day-7 after MTX.