Construction And Validation Of Endometrial Receptivity Prediction Model Based On Ultrasound Indexes

Objective: Constructing a prediction model of endometrial receptivity based on ultrasound indexes and conduct internal verification,and exploring the value of this model.Methods: Women of childbearing age who underwent in vitro fertilization in our hospital from January 1,2018 to December 31,2020 were preliminarily included as the study population.Select the appropriate population as the research object according to strict standards,and collect the general information of the research object,such as age,BMI,infertility years,menarche age,menstrual cycle,etc.at the same time,collect the parameters of endometrium measured by transvaginal ultrasound on the day of HCG injection,such as endometrial morphology,endometrial thickness,endometrial volume,endometrial and subendometrial blood flow resistance index(RI)and pulsatility index(PI),vascularization index(VI),vascularization index(FI),vascularization blood flow index(VFI),etc.According to the success of pregnancy,the subjects were divided into success group and failure group.The two groups of data were analyzed by single factor analysis.The statistically significant indicators of single factor analysis were excluded from collinearity and included in binary logistic regression analysis.At the same time,the nomogram prediction model was constructed by R software to obtain the comprehensive indicators,which were verified by internal resampling.Results: A total of 278 patients were included in this study,including 102 in the success group and 176 in the failure group.The mean intimal thickness in the success group was thicker than that in the failure group(10.77 ± 2.82 mm vs.8.89 ± 2.23mm),the intimal volume in the success group was greater than that in the failure group(4.64 ± 1.00 ml vs.3.72 ± 0.84ml),and the intimal VI,FI and VFI in the success group were higher than those in the failure group(19.81 ±3.19 vs.16.73 ± 4.00,28.43 ± 3.12 vs.24.84 ± 3.76,7.04 ± 3.21 vs.5.35 ± 2.07,respectively.The intimal RI and PI in the success group were lower than those in the failure group,which were 0.70 ± 0.16 vs.0.76 ± 0.15 and 1.22 ± 0.28 vs.1.49 ±0.26 respectively.There were significant differences between the two groups(P <0.05);There was no significant difference in other indexes.After screening,endometrial thickness,endometrial PI,VI and FI were included in multivariate analysis,and a nomogram model of endometrial receptivity was constructed to obtain comprehensive indicators.Compared with other single indexes,the comprehensive index has a larger area under the curve(Delong test)[comprehensive index AUC = 0.820,95% CI: 0.79-0.86;single index: AUC of intimal thickness = 0.669,95% CI: 0.602-0.737;FI AUC = 0.723,95% CI:0.662-0.784;PI AUC is 0.710(95% CI: 0.647-0.773),VI AUC is 0.707(95% CI:0.647-0.767)],which has high accuracy.Conclusion: Nomogram prediction model of endometrial receptivity can be constructed according to ultrasound indexes,which is feasible after internal verification;At the same time,the comprehensive index has high diagnostic efficiency,simple and practical,and is worthy of further promotion in clinical practice.