Success of the two-dose methotrexate protocol for treatment of ectopic pregnancy in women with a history of prior ectopic pregnancy.

Objective: Women with prior ectopic pregnancy (EP) have an increased failure rate when treated with single-dose methotrexate (MTX) for subsequent EP. We sought to determine whether previous EP remained a risk factor for failure when using the two-dose MTX protocol.
Study Design: Retrospective cohort study of women managed with two-dose MTX. Risk factors for MTX failure were evaluated in univariable analysis and multivariable regression modeling.
Results: A total of 234 women with EP between 1999 and 2009 were studied. Of those, 37 (15.8%) had a prior EP. In univariable analysis, prior EP was associated with a greater than twofold increased risk of MTX failure (RR 2.67, 95% CI 1.20-3.77). Higher hCG levels and ultrasound visualization of EP also increased the risk of MTX failure. In multivariable analysis hCG level remained associated with MTX failure, while prior EP did not (adjusted RR 0.97, 95% CI 0.33-2.82).
Conclusion: Prior EP is not independently associated with MTX failure in women receiving two-dose MTX therapy after controlling for known risk factors.