子宫微生物研究及其对IVF-ET助孕患者妊娠结局的影响

Uterine microbiome and its influence on pregnancy outcomes in patients undergoing IVF-ET

目的分析体外受精-胚胎移植(IVF-ET)患者的子宫微生物对妊娠结局的影响,并探讨影响子宫微生物群分布的因素。方法选取2019年10月-12月在北部战区总医院生殖医学中心行IVF-ET治疗的139例患者为研究对象。入组患者均于移植手术前做阴道微生态检查。术后从移植导管尖端及外鞘配对获取患者的子宫内膜液和宫颈粘液进行微生物培养,采用基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)鉴定宫腔和宫颈微生物。根据质谱法微生物鉴定结果并按优势菌是否为乳杆菌属菌群进行分组,即乳杆菌属主导组,非乳杆菌属主导组和鉴定阴性组。结果宫腔和宫颈菌属分布一致性尚可(Kappa=0.494)。人绒毛膜促性腺激素(HCG)阳性率在宫腔和宫颈均表现为非乳杆菌属主导组显著低于乳杆菌属主导组(60.0%vs87.2%,P<0.017;65.7%vs 97.9%,P<0.017)。着床率及临床妊娠率均在宫腔表现为非乳杆菌属主导组显著低于乳杆菌属主导组(44.7%vs 68.6%,P<0.017;52.0%vs 83.0%,P<0.017)。宫颈微生物描述着床率及临床妊娠率差异无统计学意义(P>0.017)。宫腔中检出乳杆菌属的患者其临床妊娠率显著高于未检出者(83.0%vs 65.2%,P<0.017)。移植日阴道微生态状况与E2水平是子宫微生物群分布差异的影响因素。结论当宫腔微生物以非乳杆菌属为主导时,IVF-ET助孕患者的HCG阳性率、着床率和临床妊娠率显著降低。移植日阴道微生态失调或E2过高可能增加子宫非乳杆菌属检出的风险。

Objective To analyze the influence of uterine microbiome on fertilization and embryo transfer pregnancy outcomes in vitro and the factors may affect the distribution of uterine microbiome.Methods A total of 139patients undergoing IVF-ET from Oct.to Dec.2019at the Reproductive Medicine Center of our hospital were enrolled and examined for vaginal microecology.Specimens were collected separately from the transplant catheter tip and the external sheet during embryo transfer,paired for microbial culturing and identified by using matrix-assisted laser desorption/ionization time of flight mass spectrometry.According to the results of microbial identification and dominant bacteria,the patients were divided into Lactobacillus Group,non-Lactobacillus Group and negative Group.Results There was certain consistency in the distribution between the uterine and cervical microbiome(Kappa=0.494).The positive rates of HCG in uterine cavity and cervix in non-Lactobacillus Group were both significantly lower than those in Lactobacillus Group(60.0%vs 87.2%,P<0.017;65.7%vs 87.9%,P<0.017).The implantation rate and clinical pregnancy rate in uterine cavity in non-Lactobacillus Group were both significantly lower than those in Lactobacillus Group(44.7%vs 68.6%,P<0.017;52.0%vs 82.98%,P<0.017).However,there were no significant differences in the implantation rate and clinical pregnancy rate at cervical level.Clinical pregnancy rate in patients tested positive for Lactobacillus was significantly higher than that in those with negative culturing results(83.0%vs 65.2%,P<0.017).Vaginal microecological condition and E2level on the date of transplantation were the influencing factors of the distribution of microbiome in uterus.Conclusion The presence of non-Lactobacillus dominating bacteria at the time of embryo transfer is associated with significantly decreased HCG positive rate,implantation rate and clinical pregnancy rate.Vaginal microecological disorder or excessive estradiol level on transplantation date may increase the detection rate of non-Lactobacillus bacteria.