The Impact Of Assessment Of The Uterine Cavity Environment On The Outcome Of Repeated Transplantation Failures

ObjectiveTo evaluate the impact of detection of the uterine cavity environment on the outcome of assisted pregnancy in RIF patients by detecting the uterine cavity microecology and endometrial receptivity in RIF patients,and using the results to guide transplantation.Methods1.A total of 223 patients with repeated transplantation failure who underwent IVF/ICSI-ET in the reproductive center of our hospital from September 2019 to January 2021 were selected as the research subjects.2.According to whether they received the uterine cavity microecology and receptivity test they were divided into experimental group A（n=70）,experimental group B（n=80）and control group（n=73）.Experimental group A only received uterine cavity microecology test,and experimental group B received uterine cavity microecology and endometrial receptivity test.Both groups adjusted the transplantation plan according to the results;the control group did not intervene before the transplantation cycle and applied conventional transplantation plan.3.The basic data of patients,embryo transplantation status and pregnancy outcome were compared,and the relationship between uterine cavity microbes combined with endometrial receptivity test and adjustment of transplantation medication regimen and pregnancy outcome of patients with repeated transplantation failures was analyzed.4.The subjects who received the uterine cavity microecology test（experimental group A and experimental group B）were regrouped according to whether the uterine cavity pathogens were positive or not.RIF patients with positive intrauterine pathogens were treated with corresponding antibiotics according to the positive bacterial species shown in the test results,supplemented by vaginal pretreatment with Lactobacillus;RIF patients with negative intrauterine pathogens,only pretreated with transvaginal Lactobacillus,and the pregnancy outcomes of the two groups were compared in the transplantation cycle after drug intervention.Results1.The results of 16 SrRNA sequencing showed that the average content of uterine Lactobacillus in RIF patients was 51.49 %,and the number of RIF patients with Lactobacillus content ≥90 %（defined as the uterine cavity microecology dominated by Lactobacillus）was 14（22.95 %）;the number of RIF patients with Lactobacillus content <90 %（defined as the uterine cavity microecology dominated by non-Lactobacillus）was 47（77.05 %）,and the difference was statistically significant.2.The uterine cavity bacteria of RIF patients whose uterine cavity microecology is dominated by Lactobacillus is relatively simple,and the health status and the ability to defend against other bacterial infections are stronger;in RIF patients whose uterine cavity microecology is mainly non-Lactobacillus,there were 44 transplantation cycle cases（93.62 %）showing different abundances of pathogenic bacteria,and the positive detection rate of pathogenic bacteria was significantly higher than that of RIF patients whose uterine microecology was dominated by Lactobacillus.3.In the comparison of basic data,the differences in the patient’s age,BMI,FSH,endometrial thickness on the day of transformation,and number of embryos transferred were not statistically significant in the pairwise comparisons between groups A and B and the control group.4.In the comparison of pregnancy outcomes,the embryo implantation rates of experimental group A,experimental group B and control group were 21.57 %,24.78 % and 9.09 %,respectively,and the clinical pregnancy rates were 34.43 %,39.39 % and 13.92 %,respectively.The embryo implantation rate and clinical pregnancy rate of experimental group A and experimental group B were significantly higher than those of the control group（P<0.05）;there was no significant difference in reproductive outcome between experimental group A and experimental group B.5.Subjects in experimental group A and experimental group B all received uterine cavity microecology detection,and entered the transplantation cycle after antibacterial drugs and vaginal lactobacillus pretreatment.The pathogen-negative group took medicine according to the test results,and the rates of biochemical pregnancy,embryo implantation and clinical pregnancy were higher than those in the pathogen-positive group,but the statistical results showed that there was no significant difference.Conclusion1.The majority of RIF patients with non-Lactobacillus in the uterine cavity environment,and the positive detection rate of intrauterine pathogens is significantly higher than the RIF patients with Lactobacillus-based uterine cavity microecology;2.By evaluating the uterine cavity microecology and endometrial receptivity of RIF patients,and applying antibiotics and vaginal lactobacillus pretreatment according to the test results,the uterine cavity environment during the transplantation cycle is corrected,and the pregnancy outcome of RIF patients is determined.improvement is positive,which can significantly improve the pregnancy outcome of RIF patients.;3.Vaginal pretreatment with Lactobacillus before the transplantation cycle of RIF patients can alleviate the imbalance of uterine flora and improve the reproductive outcome of RIF patients.Compared with high-throughput sequencing technology,it is economical and convenient.It has great clinical translation value.