Is a foetus developing in a sterile environment?

@article{Wassenaar2014IsAF,
  title={Is a foetus developing in a sterile environment?},
  author={Trudy M. Wassenaar and Pinaki Panigrahi},
  journal={Letters in Applied Microbiology},
  year={2014},
  volume={59}
}
Novel findings in microbiology question the long‐standing paradigm that a healthy pregnancy implies a sterile uterus. It now seems that the placenta is frequently colonized with bacteria, and a placental microbiome has been identified. Recent literature findings are summarized here, and an attempt is made to separate pathological bacterial presence from a naturally occurring microbiome. 
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95 Citations
Highly Influential Citations
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Background Citations
37
Methods Citations
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95 Citations

Citation Type

Citation Type

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TLDR
There is much uncertainty in the method of hematogenous bacterial transmission to the placenta, but research has begun to suggest that a low abundance of bacteria in thePlacenta does not harm the fetus, and may be present more often than previously believed.
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Current scientific evidence does not support the existence of microbiomes within the healthy fetal milieu, which has implications for the development of clinical practices that prevent microbiome perturbations after birth and the establishment of future research priorities.
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  • Medicine
    The Canadian journal of infectious diseases & medical microbiology = Journal canadien des maladies infectieuses et de la microbiologie medicale
  • 2015
TLDR
This study assessed the similarities in the bacterial species detected in the infant’s first feces with samples obtained from the mother's placenta and vagina to assess the initial colonization of a newborn infant.
Vaginal microbiomes and ovarian cancer: a review.
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The latest research in knowledge regarding the association between the vaginal microbiomes and oncogenesis is reviewed, with a particular focus on ovarian carcinoma.
The Microbiota of the Extremely Preterm Infant
The Evolving Microbiome from Pregnancy to Early Infancy: A Comprehensive Review
TLDR
The present review summarizes the actual knowledge related to physiological changes in the microbiota occurring in the mother, the fetus, and the child, both during neonatal period and beyond, as well as the influence of the type of delivery and feeding.
Safely unsterile : understanding the anatomical and immunologic niches of placental , urinary and vaginal microbiomes
TLDR
Comparing the placenta, urinary tract and vagina microbiomes illustrates that neither microbial sterility nor constancy have been observed in healthy populations and highlights the ubiquitous role that microorganisms play in normal human physiology.
Bacterial Communities in the Womb During Healthy Pregnancy
TLDR
Culture-based investigation of amniotic fluid and placenta samples confirmed the presence of cultivable microorganisms in theplacenta but not in amniosis fluid, suggesting that bacterial colonization does occur during healthy pregnancy.
A Dormant Microbial Component in the Development of Preeclampsia
TLDR
The recognition of an infectious component in the etiology of PE mirrors that for ulcers and other diseases that were previously considered to lack one and suggests a number of treatments, some of which have, in fact, been shown to be successful.
Is there evidence for bacterial transfer via the placenta and any role in the colonization of the infant gut? – a systematic review
TLDR
Current data are limited and provide no conclusive evidence that there is a normal placental microbiome which has any role in colonization of infant gut.
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