Objective: Our study aimed to investigate the predisposing factors for recurrence of an ectopic pregnancy (EP) following single-dose methotrexate (MTX) treatment for a primary EP. Methods: This was a retrospective cohort study performed in a tertiary care medical centre including all patients diagnosed with primary EP and treated with a single-dose regimen of intramuscular MTX. EPs with future recurrence were compared with first time only EPs, to identify risk factors for recurrent EP. Forward stepwise multivariate logistic regression analyses were subsequently carried out. Results: The study included 272 women. Of those, 22 (8.1%) had a recurrent EP. Women in the recurrent EP group had a higher rate of abortions (45.5% vs 32.7%; p = 0.02), previous pelvic surgery (45.5% vs 6.5%; p < 0.001) and both pelvic and uterine surgery (4.5% vs 1.6%; p < 0.001). Conception by assisted reproductive technology (ART) was more common among the non-recurrent EP group (23.0% vs 4.5%; p = 0.04). Success of single-dose MTX treatment was lower in the recurrent EP group compared with the non-recurrent EP group (36.4% vs 65.7%; p = 0.006). A history of pelvic surgery was independently associated with recurrent EP (adjusted odds ratio [OR] 17.6; 95% confidence interval [CI] 4.9, 63.2; p = 0.001). Treatment success of single-dose MTX was independently protective for recurrent EP (adjusted OR 0.25; 95% CI 0.08, 0.76; p = 0.02). Conclusions: Among women with an EP, attention should be paid to those with previous pelvic surgery. Efforts should be made to achieve medical treatment success to prevent recurrent EP.
Keywords: Assisted reproductive technology; complications; ectopic pregnancy; methotrexate; recurrent ectopic pregnancy.