ArticleBJOG : an international journal of obstetrics and gynaecology2020
The association between vaginal bacterial composition and miscarriage: a nested case-control study.
Article in BJOG : an international journal of obstetrics and gynaecology, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 77 papers, 2 of them syntheses that pooled it.
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Who cites it
77 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- Microbiota composition of the female reproductive tract and miscarriage: a systematic review and meta-analysis.NPJ biofilms and microbiomes · 2026Pooled it
- The Predictive Significance of Platelet-to-Lymphocyte Ratio for Miscarriage: A Systematic Review and Meta-Analysis.Immunity, inflammation and disease · 2025Pooled it
- Gut microbiome and pregnancy complications: emerging evidence and mechanistic insights.Gut microbes · 2026Review
- The Impact of First-Trimester Vaginal Microecology on Spontaneous Abortion: A Retrospective Cohort Study.Pathogens (Basel, Switzerland) · 2026Article
- Selective Human-Milk-Inspired Antimicrobial Peptides for the Treatment of Bacterial Vaginosis.Pharmaceutics · 2026Article
- Machine learning and the role of the vaginal and fecal microbiome in miscarriage: a matched case-control study.NPJ biofilms and microbiomes · 2026Article
- Anti-β2GPI/HLA-DR Antibody, Chronic Endometritis, and Uterine Endometrial Microbiome in Women with Recurrent Pregnancy Loss: A Prospective Cohort Study.Microorganisms · 2026Article
- Clinical significance of plasma SERPINA3 in patients with missed miscarriage.Frontiers in medicine · 2026Article
- Progesterone in recurrent pregnancy loss: from controversial efficacy to mechanism-based patient stratification.Frontiers in pharmacology · 2026Review
- Microbial regulators of physiological and reproductive health in women of reproductive age: their local, proximal and distal regulatory roles.NPJ biofilms and microbiomes · 2025Review
- Correlation between Lactobacillus of Vaginal Microbiota and the Pregnancy Outcomes for Patients Experiencing Recurrent Miscarriage.Reproductive sciences (Thousand Oaks, Calif.) · 2025Article
- Endometrial microbiome in reproductive failure: The possibility of metagenomic analysis.Clinical and experimental reproductive medicine · 2025Article
- Review
- Exploring the Immunological Aspects and Treatments of Recurrent Pregnancy Loss and Recurrent Implantation Failure.International journal of molecular sciences · 2025Review
- The untapped potential of vaginal microbiome diagnostics for improving women's health.Frontiers in cellular and infection microbiology · 2025Review
- The Safety of Probiotics Intended for Use in Pregnant and Lactating Women: From a Desirable to a Required Task.Foods (Basel, Switzerland) · 2024Review
- The Role of the Vaginal and Endometrial Microbiomes in Infertility and Their Impact on Pregnancy Outcomes in Light of Recent Literature.International journal of molecular sciences · 2024Review
- Secretor status is a modifier of vaginal microbiota-associated preterm birth risk.Microbial genomics · 2024Article
- A prospective cohort study examining the association between the periconceptual vaginal microbiota and first-trimester miscarriage in Kenyan women.Paediatric and perinatal epidemiology · 2024Article
- Microbiota and Recurrent Pregnancy Loss (RPL); More than a Simple Connection.Microorganisms · 2024Review
17 more citing papers are in PubMed but not listed here.
Corrections and comments
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Authors and funding
11 authors.
Funding
Abstract
objectiveTo characterise vaginal bacterial composition in early pregnancy and investigate its relationship with first and second trimester miscarriages.
designNested case-control study.
settingQueen Charlotte's and Chelsea Hospital, Imperial College Healthcare NHS Trust, London. POPULATION: 161 pregnancies: 64 resulting in first trimester miscarriage, 14 in second trimester miscarriage and 83 term pregnancies.
methodsProspective profiling and comparison of vaginal bacteria composition using 16S rRNA gene-based metataxonomics from 5 weeks' gestation in pregnancies ending in miscarriage or uncomplicated term deliveries matched for age, gestation and body mass index.
main outcome measuresRelative vaginal bacteria abundance, diversity and richness. Pregnancy outcomes defined as first or second trimester miscarriage, or uncomplicated term delivery.
resultsFirst trimester miscarriage associated with reduced prevalence of Lactobacillus spp.-dominated vaginal microbiota classified using hierarchical clustering analysis (65.6 versus 87.7%; P = 0.005), higher alpha diversity (mean Inverse Simpson Index 2.5 [95% confidence interval 1.8-3.0] versus 1.5 [1.3-1.7], P = 0.003) and higher richness 25.1 (18.5-31.7) versus 16.7 (13.4-20), P = 0.017), compared with viable pregnancies. This was independent of vaginal bleeding and observable before first trimester miscarriage diagnosis (P = 0.015). Incomplete/complete miscarriage associated with higher proportions of Lactobacillus spp.-depleted communities compared with missed miscarriage. Early pregnancy vaginal bacterial stability was similar between miscarriage and term pregnancies.
conclusionsThese findings associate the bacterial component of vaginal microbiota with first trimester miscarriage and indicate suboptimal community composition is established in early pregnancy. While further studies are required to elucidate the mechanism, vaginal bacterial composition may represent a modifiable risk factor for first trimester miscarriage. TWEETABLE ABSTRACT: Vaginal bacterial composition in first trimester miscarriage is associated with reduced Lactobacillus spp. abundance and is independent of vaginal bleeding.
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