OBJECTIVE To estimate predictive factors for failure of laparoscopic conservative treatment of ectopic pregnancy using a standardized surgical technique. METHODS We performed a population-based study from the Auvergne ectopic pregnancy registry. A total of 3,196 cases of ectopic pregnancy were registered between 1992 and 2008. Among conservative treatments (n=1,965), 1,306 (66.5%) patients underwent laparoscopic salpingostomy exclusively. For each case, collected data included: sociodemographic characteristics, previous surgeries, gynecologic and reproductive histories, conditions of conception, Chlamydiae trachomatis serology, human chorionic gonadotropin (hCG) levels, and ectopic pregnancy characteristics. Univariable and multivariable analyses were performed to identify risk factors for treatment. A receiver operating characteristic curve was also provided. Statistical significance was established at P<.05. RESULTS We identified 86 treatment failures (6.6%). The failure rate remained stable through the study period. Pretherapeutic hCG level was the only factor significantly associated with treatment failure. Patients with an hCG level of at least 1,960 international units/L had a failure rate of 8.6% compared with 5.1% in patients with a lower hCG level (P=.03). Sensitivity and specificity of this cutoff limit were 47% and 67%, respectively (likelihood ratio(+)=1.4 and likelihood ratio(-)=0.8). CONCLUSIONS The hCG level of at least 1,960 international units/L is the only factor related to treatment failure. However, the prognostic value of this cutoff is low and with limited clinical relevance. METHODS II.