Construction of A Nomogram Model for Predicting Massive Hemorrhage during Hysteroscopic Cureage in Cesarean Scar Pregnancy and Risk Stratification Based on Multimodal Ultrasound Parameters

LI Qian; DAI Chengcheng; ZHANG Junhui; WANG Min; WU Tong

doi:10.3969/j.issn.1002-3429.2025.14.010

Abstract：Objective To construct a Nomogram model for predicting massive hemorrhage during hysteroscopic curettage in cesarean scar pregnancy(CSP)based on multimodal ultrasound parameters.Methods Taking CSP,uterine scar pregnancy,cesarean uterine scar pregnancy,and hysteroscopic uterine curettage as search terms,the VIP Chinese Science and Technology Journal Database,China National Knowledge Infrastructure(CNKI),and Wanfang Database from January 2021 to August 2024 were retrieved.A total of 244 patients with CSP who underwent hysteroscopic uterine curettage were obtained as the modeling set.According to the amount of bleeding during hysteroscopic uterine curettage,the patients were divided into the massive hemorrhage group(n=60)and the non-massive hemorrhage group(n=184).A total of 105 CSP patients who underwent hysteroscopic uterine curettage and were admitted to Dezhou Hospital,Qilu Hospital of Shandong University at a ratio of 7∶3 during the same period were selected as the validation set.Multivariate logistic regression analysis was conducted to analyze the influencing factors of massive hemorrhage during hysteroscopic uterine curettage for CSP.The Nomogram model was constructed for model validation to evaluate the discrimination,consistency and clinical efficacy of the model.Further,the recursive segmentation method was used for risk stratification of massive hemorrhage.Results Multivariate logistic regression analysis showed that the maximum diameter of the gestational sac,the thickness of the chorion in the anterior isthmus,the thickness of the residual muscular layer,the vascularization index(VI),and the blood flow grading were all influencing factors of massive hemorrhage during hysteroscopic uterine curettage for CSP(P<0.05).Based on the results of multivariate logistic regression analysis,a Nomogram model of massive hemorrhage during CSP hysteroscopic curettage was constructed.The external validation of receiver operating characteristic(ROC)curve showed that the areas under the curve of this model for predicting massive hemorrhage during hysteroscopic uterine curettage for CSP in the modeling set and validation set were 0.906 and 0.933,respectively.The calibration curve showed that the risk of massive hemorrhage predicted by this model in the modeling set and validation set during hysteroscopic curettage for CSP was basically consistent with the actual risk situation.The evaluation of the decision curve showed that the clinical utility of this model was relatively high.Risk stratification showed that the incidence of massive hemorrhage during hysteroscopic curettage in high-risk CSP was 51.25%,which was higher than 13.64%in medium-risk and 9.21%in low-risk CSP,and the difference was statistically significant(P<0.01).Conclusion Massive hemorrhage during hysteroscopic curettage in patients with CSP is related to factors such as the maximum diameter of the gestational sac,the thickness of the chorion in the anterior isthmus,the thickness of the residual muscular layer,VI,and blood flow grading.The Nomogram model constructed based on this is beneficial for predicting massive hemorrhage during hysteroscopic curettage in patients with CSP.Moreover,the risk stratification system of this model has certain clinical value in differentiating the risk of massive hemorrhage during hysteroscopic curettage for CSP.