{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,13]],"date-time":"2025-10-13T06:10:45Z","timestamp":1760335845861,"version":"build-2065373602"},"reference-count":27,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,10,13]],"date-time":"2025-10-13T00:00:00Z","timestamp":1760313600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Cell. Infect. Microbiol."],"abstract":"<jats:sec><jats:title>Introduction<\/jats:title><jats:p>Recurrent pregnancy loss (RPL) is a complex condition with multifactorial causes. This study aimed to characterize the microbial composition of endometrial fluid in RPL patients compared with healthy controls.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>A total of 114 participants were recruited from the Second Hospital of Lanzhou University between March and September 2023, including 68 RPL patients and 46 healthy controls. Clinical data and endometrial fluid samples were collected. Microbial DNA was extracted and analyzed using 16S rRNA gene sequencing. Microbial diversity was assessed with QIIME, semi-partial correlation analysis was applied to explore associations between groups, and LEfSe was used to identify differentially abundant taxa.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>No significant differences in alpha diversity indices were found between the groups (p&amp;gt;0.05). However, beta diversity showed significant differences (p&amp;lt;0.05), indicating distinct microbial compositions. At the genus level, <jats:italic>Vibrio<\/jats:italic> and <jats:italic>Pseudoalteromonas<\/jats:italic> were positively correlated with RPL, suggesting their potential role in the condition. LEfSe analysis further validated our results, highlighting several taxa with significant differences in abundance, indicating microbial imbalances in RPL patients.<\/jats:p><\/jats:sec><jats:sec><jats:title>Discussion<\/jats:title><jats:p>The study emphasizes the impact of microbial imbalances on reproductive health, potentially aiding in the development of targeted interventions to restore microbial balance and improve pregnancy outcomes in RPL patients.<\/jats:p><\/jats:sec>","DOI":"10.3389\/fcimb.2025.1646125","type":"journal-article","created":{"date-parts":[[2025,10,13]],"date-time":"2025-10-13T05:28:03Z","timestamp":1760333283000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Analysis of the characteristics of endometrial fluid samples in recurrent pregnancy loss patients based on 16S rRNA gene sequencing technology"],"prefix":"10.3389","volume":"15","author":[{"given":"Xiaoping","family":"Wang","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nan","family":"Ding","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaofeng","family":"Li","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Menghao","family":"Lu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Peili","family":"Wang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2025,10,13]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"431","DOI":"10.1007\/s10126-022-10097-0","article-title":"Molecular relationships in biofilm formation and the biosynthesis of exoproducts in pseudoalteromonas spp","volume":"24","author":"Alviz-Gazitua","year":"2022","journal-title":"Mar. Biotechnol. (NY)."},{"key":"B2","doi-asserted-by":"publisher","first-page":"hoy004","DOI":"10.1093\/hropen\/hoy004","article-title":"ESHRE guideline: recurrent pregnancy loss","volume":"2018","author":"Bender Atik","year":"2018","journal-title":"Hum. Reprod. Open"},{"key":"B3","doi-asserted-by":"publisher","first-page":"12787","DOI":"10.3390\/ijms232112787","article-title":"Endometrium immunomodulation to prevent recurrent implantation failure in assisted reproductive technology","volume":"23","author":"Benkhalifa","year":"2022","journal-title":"Int. J. Mol. Sci."},{"key":"B4","doi-asserted-by":"publisher","first-page":"393","DOI":"10.1093\/humupd\/dmy012","article-title":"How uterine microbiota might be responsible for a receptive, fertile endometrium","volume":"24","author":"Benner","year":"2018","journal-title":"Hum. Reprod. Update"},{"key":"B5","doi-asserted-by":"publisher","first-page":"57","DOI":"10.1038\/nmeth.2276","article-title":"Quality-filtering vastly improves diversity estimates from Illumina amplicon sequencing","volume":"10","author":"Bokulich","year":"2013","journal-title":"Nat. Methods"},{"key":"B6","doi-asserted-by":"publisher","first-page":"93","DOI":"10.1186\/s12864-016-3382-y","article-title":"The pangenome of (Antarctic) Pseudoalteromonas bacteria: evolutionary and functional insights","volume":"18","author":"Bosi","year":"2017","journal-title":"BMC Genomics"},{"key":"B7","doi-asserted-by":"publisher","DOI":"10.3389\/fcimb.2021.631972","article-title":"The female vaginal microbiome in health and bacterial vaginosis","volume":"11","author":"Chen","year":"2021","journal-title":"Front. Cell Infect. Microbiol."},{"key":"B8","doi-asserted-by":"publisher","first-page":"1937015","DOI":"10.1080\/19490976.2021.1937015","article-title":"The interface of vibrio cholerae and the gut microbiome","volume":"13","author":"Cho","year":"2021","journal-title":"Gut. Microbes"},{"key":"B9","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2020.528202","article-title":"Recent insights on the maternal microbiota: impact on pregnancy outcomes","volume":"11","author":"Di Simone","year":"2020","journal-title":"Front. Immunol."},{"key":"B10","doi-asserted-by":"publisher","first-page":"939","DOI":"10.1016\/j.rbmo.2021.02.003","article-title":"Impact of chronic endometritis in infertility: a SWOT analysis","volume":"42","author":"Espin\u00f3s","year":"2021","journal-title":"Reprod. BioMed. Online"},{"key":"B11","doi-asserted-by":"publisher","first-page":"129","DOI":"10.1007\/s10815-015-0614-z","article-title":"Endometrial microbiome at the time of embryo transfer: next-generation sequencing of the 16S ribosomal subunit","volume":"33","author":"Franasiak","year":"2016","journal-title":"J. Assist. Reprod. Genet."},{"key":"B12","doi-asserted-by":"publisher","first-page":"622","DOI":"10.3390\/ijms25010622","article-title":"Clinical relevance of vaginal and endometrial microbiome investigation in women with repeated implantation failure and recurrent pregnancy loss","volume":"25","author":"Gao","year":"2024","journal-title":"Int. J. Mol. Sci."},{"key":"B13","doi-asserted-by":"publisher","DOI":"10.3389\/frph.2022.963752","article-title":"The female reproductive tract microbiotas, inflammation, and gynecological conditions","volume":"4","author":"Gholiof","year":"2022","journal-title":"Front. Reprod. Health"},{"key":"B14","doi-asserted-by":"publisher","first-page":"1540","DOI":"10.3390\/medicina59091540","article-title":"The endometrial microbiota: challenges and prospects","volume":"59","author":"Kaluanga Bwanga","year":"2023","journal-title":"Med. (Kaunas)."},{"key":"B15","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2022.826198","article-title":"Multiomics studies investigating recurrent pregnancy loss: an effective tool for mechanism exploration","volume":"13","author":"Li","year":"2022","journal-title":"Front. Immunol."},{"key":"B16","doi-asserted-by":"publisher","first-page":"304","DOI":"10.1016\/j.fertnstert.2024.03.007","article-title":"World Endometriosis Research Foundation Endometriosis Phenome and Biobanking Harmonization Project: V. Physical examination standards in endometriosis research","volume":"122","author":"Lin","year":"2024","journal-title":"Fertil. Steril."},{"key":"B17","doi-asserted-by":"publisher","first-page":"684","DOI":"10.1016\/j.ajog.2016.09.075","article-title":"Evidence that the endometrial microbiota has an effect on implantation success or failure","volume":"215","author":"Moreno","year":"2016","journal-title":"Am. J. Obstet. Gynecol."},{"key":"B18","doi-asserted-by":"publisher","first-page":"296","DOI":"10.1016\/j.ajog.2020.01.031","article-title":"The first glimpse of the endometrial microbiota in early pregnancy","volume":"222","author":"Moreno","year":"2020","journal-title":"Am. J. Obstet. Gynecol."},{"key":"B19","doi-asserted-by":"publisher","first-page":"98","DOI":"10.1080\/25785826.2020.1809951","article-title":"Harmful and beneficial effects of inflammatory response on reproduction: sterile and pathogen-associated inflammation","volume":"44","author":"Negishi","year":"2021","journal-title":"Immunol. Med."},{"key":"B20","doi-asserted-by":"publisher","first-page":"638","DOI":"10.1093\/humrep\/dead274","article-title":"The endometrial microbiota and early pregnancy loss","volume":"39","author":"Odendaal","year":"2024","journal-title":"Hum. Reprod."},{"key":"B21","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2023.1306473","article-title":"Microbiota dynamics, metabolic and immune interactions in the cervicovaginal environment and their role in spontaneous preterm birth","volume":"14","author":"Onyango","year":"2023","journal-title":"Front. Immunol."},{"key":"B22","doi-asserted-by":"publisher","first-page":"48","DOI":"10.1186\/s40168-017-0268-4","article-title":"A critical assessment of the \u201csterile womb\u201d and \u201cin utero colonization\u201d hypotheses: implications for research on the pioneer infant microbiome","volume":"5","author":"Perez-Mu\u00f1oz","year":"2017","journal-title":"Microbiome"},{"key":"B23","doi-asserted-by":"publisher","first-page":"1021","DOI":"10.1016\/j.rbmo.2022.06.008","article-title":"Female reproductive tract microbiota and recurrent pregnancy loss: a nested case-control study","volume":"45","author":"Peuranp\u00e4\u00e4","year":"2022","journal-title":"Reprod. BioMed. Online"},{"key":"B24","doi-asserted-by":"publisher","first-page":"546","DOI":"10.1016\/j.fertnstert.2020.12.010","article-title":"Endometrial causes of recurrent pregnancy losses: endometriosis, adenomyosis, and chronic endometritis","volume":"115","author":"Pirtea","year":"2021","journal-title":"Fertil. Steril."},{"key":"B25","doi-asserted-by":"publisher","first-page":"2391","DOI":"10.3390\/biomedicines11092391","article-title":"Chronic endometritis and uterine endometrium microbiota in recurrent implantation failure and recurrent pregnancy loss","volume":"11","author":"Takimoto","year":"2023","journal-title":"Biomedicines"},{"key":"B26","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2022.994888","article-title":"Decidual macrophages in recurrent spontaneous abortion","volume":"13","author":"Zhao","year":"2022","journal-title":"Front. Immunol."},{"key":"B27","doi-asserted-by":"publisher","first-page":"e0018121","DOI":"10.1128\/mmbr.00181-21","article-title":"Roles of the microbiota of the female reproductive tract in gynecological and reproductive health","volume":"86","author":"Zhu","year":"2022","journal-title":"Microbiol. Mol. Biol. Rev."}],"container-title":["Frontiers in Cellular and Infection Microbiology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fcimb.2025.1646125\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,13]],"date-time":"2025-10-13T05:28:03Z","timestamp":1760333283000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fcimb.2025.1646125\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,10,13]]},"references-count":27,"alternative-id":["10.3389\/fcimb.2025.1646125"],"URL":"https:\/\/doi.org\/10.3389\/fcimb.2025.1646125","relation":{},"ISSN":["2235-2988"],"issn-type":[{"type":"electronic","value":"2235-2988"}],"subject":[],"published":{"date-parts":[[2025,10,13]]},"article-number":"1646125"}}