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bioRxiv · 10.1101/659797

Placenta microbiome diversity is associated with maternal pre-pregnancy obesity and placenta biogeography

Benny, P.·Al-Akwa, F.·Dirks, C.·Schlueter, R.·Wolfgruber, T.·Chern, I.·Hoops, S.·Knights, D.·Garmire, L.
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Abstract

Recently there has been considerable debate in the scientific community regarding the placenta as the host of a unique microbiome. No studies have addressed the associations of clinical conditions such as maternal obesity, or localizations on the placental microbiome. We examined the placental microbiome in a multi-ethnic maternal pre-pregnant obesity cohort using controls for environmental contaminants and an optimized microbiome protocol to enrich low bacterial biomass samples. We confirmed that a distinct placenta microbiome does exist, as compared to the environmental background. The placenta microbiome consists predominantly of Lactobacillus, Enterococcus and Chryseobacterium. Moreover, the microbiome in the placentas of obese pre-pregnant mothers are less diverse when compared to those of mothers of normal pre-pregnancy weight. Lastly, microbiome richness also decreases from the maternal side to fetal side. In summary, our study reveals associations of placental microbiome with placenta biogeography and with maternal pre-pregnant obesity.

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Benny, P., Al-Akwa, F., Dirks, C., Schlueter, R., Wolfgruber, T., Chern, I., Hoops, S., Knights, D., Garmire, L.. 2019-06-04. Placenta microbiome diversity is associated with maternal pre-pregnancy obesity and placenta biogeography. https://doi.org/10.1101/659797

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