超声引导下局部注射甲氨蝶呤治疗剖宫产瘢痕妊娠失败的预测因素及其风险分层分析OA

Objective To investigate the independent predictive factors for the failure of methotrexate(MTX)in treating gestational sac-type cesarean scar pregnancy(CSP),and to construct and preliminarily validate a risk stratification prediction model.Methods The clinical data of 55 patients with gestational sac-type CSP who underwent ultrasound-guided local MTX injection at the First Medical Center of PLA General Hospital between January 2014 and June 2025 were retrospectively analyzed.Patients were divided into successful drug treatment group(n=41)and failed drug treatment group(n=14)according to whether surgical intervention was required after treatment.Univariate and multivariate logistic regression analyses were performed to identify independent predictive factors for MTX treatment failure.A risk stratification model was constructed based on these predictors.The area under the receiver operating characteristic(ROC)curve(AUC)was calculated,and internal validation was conducted using the Bootstrap method(1000 repeated samplings)to assess the discriminatory power and stability of the model.Results The overall success rate of MTX treatment was 74.5%(41/55).Univariate analysis showed significant associations between treatment failure and Jordans classification(P=0.036),embryonic bud grouping(P=0.008),preoperative serum β-human chorionic gonadotropin(β-hCG)(P=0.009),and mean gestational sac diameter(P=0.026).Multivariate logistic regression analysis revealed that Jordans type Ⅱ(OR=5.318,95%CI 1.030-27.446,P=0.046)and embryonic bud length≥4.0 mm(OR=10.893,95%CI 2.233-53.138,P=0.003)were independent predictive factors for treatment failure.Based on these results,CSP patients were stratified into three groups:low-risk group(Jordans type Ⅰ+embryonic bud length<4.0 mm),intermediate-risk group(Jordans type Ⅰ+embryonic bud length≥4.0 mm or Jordans type Ⅱ+embryonic bud length<4.0 mm),and high-risk group(Jordans type Ⅱ+embryonic bud length≥4.0 mm).The actual failure rate was 3.8%(1/26)in low-risk group(n=26),25.0%(6/24)in intermediate-risk group(n=24),and 80.0%(4/5)in high-risk group(n=5).ROC analysis demonstrated that the model had moderate discriminatory power(AUC=0.780),and Bootstrap validation confirmed good stability of the model with a mean AUC of 0.782(95%CI 0.632-0.904)and a median AUC of 0.788(0.740,0.832).Conclusions Jordans classification and embryonic bud length are important indicators for predicting the treatment failure of ultrasound-guided local MTX injection in gestational sac-type CSP.The preliminary risk stratification model based on these predictors provides a decision-making reference for the individualized treatment of CSP.