Embryonic miscarriage severely affects the life quality and physical and mental state of pregnant women. However, the detailed mechanism underlying embryonic miscarriage is not fully understood. This study is aimed at analyzing embryonic miscarriage. We collected samples from 25 normal pregnant women and 25 embryonic miscarriage patients of similar age to analyze microbiota isolated from the vagina. Crude examination of the vagina isolates showed that compared with the control group, 80% of the embryonic miscarriage group contained a significantly lower number of Lactobacillus, the major healthy microbe in the vagina. Furthermore, the levels of Th1 and Th2 secreted cytokine interleukin 2 (IL-2) and interleukin10 (IL-10), respectively, were examined. Results showed that the IL2 level was higher, and IL10 level was lower in the embryonic miscarriage group than in the control group, whereas the IL2/IL10 level was higher in the embryonic miscarriage group than in the control group. This finding suggested that the immune response was suppressed in the embryonic miscarriage group. To further dissect the microbiota of the vagina in the two groups, 16S rDNA sequencing was performed. Bioinformatics analysis showed that 1096 and 998 overlapped operational taxonomic units were identified from the embryonic miscarriage and control groups, respectively. At the genus level, the relative abundance of Fam_Finegoldia, Lac_Coprococcus_3, and Lac_Roseburia significantly differed in the embryonic miscarriage group. Overall, our analyses provided potential biomarkers for embryonic miscarriage and elucidated the causative relationship between microbiota and immune responses and may enable the possible diagnosis and therapeutics of early pregnancy loss.

中文翻译：

---

16S rDNA高通量测序的胚胎流产患者阴道菌群多样性

胚胎流产严重影响孕妇的生活质量和身心状况。但是，胚胎流产的详细机制尚不完全清楚。这项研究旨在分析胚胎流产。我们收集了25位正常孕妇和25位年龄相近的胚胎流产患者的样本，以分析从阴道分离出的微生物群。阴道分离物的粗略检查显示，与对照组相比，胚胎流产组中80％的乳酸菌数量明显减少，阴道中的主要健康微生物。此外，还检查了Th1和Th2分泌的细胞因子白介素2（IL-2）和白介素10（IL-10）的水平。结果显示，胚胎流产组的IL2水平较高，IL10水平低于对照组，而胚胎流产组的IL2 / IL10水平高于对照组。该发现表明在胚胎流产组中免疫应答被抑制。为了进一步剖析两组的阴道微生物群，进行了16S rDNA测序。生物信息学分析表明，从胚胎流产组和对照组中分别鉴定出1096个和998个重叠的操作分类单位。在属水平上，Fam_Finegoldia，Lac_Coprococcus_3，和Lac_Roseburia在胚胎流产组中有显着差异。总的来说，我们的分析为胚胎流产提供了潜在的生物标志物，阐明了微生物群与免疫反应之间的因果关系，并可能为早期流产提供可能的诊断和治疗方法。