ArticlePloS one2020
Evidence for contamination as the origin for bacteria found in human placenta rather than a microbiota.
Article in PloS one, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 34 papers.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
34 citing papers in PubMed, 55 citations in OpenAlex.
- Unraveling Oral Dysbiosis: Microbial Complexity in Common Oral Diseases.MicrobiologyOpen · 2026Review
- Methodological bias shapes the interpretation of the urinary microbiome in low-biomass systems.Frontiers in microbiology · 2026Review
- Gut-placenta axis: gut microbiota metabolites may play a role in regulating maternal-fetal immune tolerance and the pathogenesis of adverse pregnancy outcomes.Frontiers in immunology · 2026Review
- Maternal microbiota and fetal brain development: a multidisciplinary review of cognitive, neurological, and metabolic outcomes.Frontiers in neurology · 2026Review
- Microbiome diversity of low biomass skin sites is captured by metagenomics but not 16S amplicon sequencing.bioRxiv : the preprint server for biology · 2025Article
- Bacterial DNA detection in blood using PCR/ESI-MS in neonates with suspected early onset infection.Frontiers in cellular and infection microbiology · 2025Observational
- Analysis of metagenomic data.Nature reviews. Methods primers · 2025Article
- A microbial symphony: a literature review of the factors that orchestrate the colonization dynamics of the human colonic microbiome during infancy and implications for future health.Microbiome research reports · 2025Review
- Evaluation of the Human Placental Microbiota in Early- and Late-Onset Pre-Eclampsia.High blood pressure & cardiovascular prevention : the official journal of the Italian Society of Hypertension · 2024Article
- Review
- Targeted Metagenomic Databases Provide Improved Analysis of Microbiota Samples.Microorganisms · 2024Article
- Review and Perspectives onMicroorganisms · 2023Review
- Microbial diversity in the vaginal microbiota and its link to pregnancy outcomes.Scientific reports · 2023Article
- Multi-factorial examination of amplicon sequencing workflows from sample preparation to bioinformatic analysis.BMC microbiology · 2023Article
- Comparative Analysis of the Placental Microbiome in Pregnancies with Late Fetal Growth Restriction versus Physiological Pregnancies.International journal of molecular sciences · 2023Article
- Is there a placental microbiota? A critical review and re-analysis of published placental microbiota datasets.BMC microbiology · 2023Review
- Amplification of microbial DNA from bacterial extracellular vesicles from human placenta.Frontiers in microbiology · 2023Article
- Editorial: Contribution of the maternal microbiome to offspring health.Frontiers in nutrition · 2023Article
- Assessment of the human placental microbiome in early pregnancy.Frontiers in medicine · 2023Article
- Vaginal microbiota in women with spontaneous preterm labor versus those with term labor in Kenya: a case control study.BMC microbiology · 2022Article
Corrections and comments
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Authors and funding
8 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Until recently the in utero environment of pregnant women was considered sterile. Recent high-sensitivity molecular techniques and high-throughput sequencing lead to some evidence for a low-biomass microbiome associated with the healthy placenta. Other studies failed to reveal evidence for a consistent presence of bacteria using either culture or molecular based techniques. Comparing conflicting "placental microbiome" studies is complicated by the use of varied and inconsistent protocols. Given this situation, we undertook an evaluation of the in utero environment sterility using several controlled methods, in the same study, to evaluate the presence or absence of bacteria and to explain contradictions present in the literature. Healthy pregnant women (n = 38) were recruited in three maternity wards. Placenta were collected after cesarean section with or without Alexis® and vaginal delivery births. For this study we sampled fetal membranes, umbilical cord and chorionic villi. Bacterial presence was analyzed using bacterial culture and qPCR on 34 fetal membranes, umbilical cord and chorionic villi samples. Shotgun metagenomics was performed on seven chorionic villi samples. We showed that the isolation of meaningful quantities of viable bacteria or bacterial DNA was possible only outside the placenta (fetal membranes and umbilical cords) highlighting the importance of sampling methods in studying the in utero environment. Bacterial communities described by metagenomics analysis were similar in chorionic villi samples and in negative controls and were dependent on the database chosen for the analysis. We conclude that the placenta does not harbor a specific, consistent and functional microbiota.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.