Previous ectopic pregnancy as a predictor of failure of systemic methotrexate therapy

Abstract

Objective To investigate whether a history of previous ectopic pregnancy is an independent risk factor for failure of methotrexate therapy in subsequent ectopic pregnancies and whether the previous treatment method influenced failure. Setting Inner-city teaching hospital. Design Retrospective case review. Patient(s) Five hundred four consecutive patients treated with “single-dose” methotrexate for ectopic pregnancy. Nine patients electing surgery after beginning medical therapy were excluded from analysis. Intervention(s) Systemic methotrexate 50 mg/m 2. Main outcome measure(s) Failure of methotrexate therapy. Result(s) Twenty-one (18.6%) of 113 of previous ectopic patients and 26 (6.8%) of 382 first-time ectopic patients failed methotrexate therapy (odds ratio, 3.12). The overall success rate was 90.5% (448/495 patients). Univariant analysis showed that treatment hCG and progesterone (P) levels and ectopic cardiac activity were significantly different between successful and failed therapy. Logistic regression analysis for these four variables showed that only hCG and history of previous methotrexate remained significant risk factors for failure of methotrexate therapy. The likelihood of failure in patients with a previous ectopic was not influenced by previous treatment with salpingostomy, salpingectomy, or medical treatment. Conclusion(s) A history of previous ectopic pregnancy appears to be an independent risk factor for failure of systemic methotrexate treatment, but failure is not affected by previous treatment method.