The meconium microbiota shares more features with the amniotic fluid microbiota than the maternal fecal and vaginal microbiota

Abstract

The early-life gut microbiota is associated with potential development of diseases in adulthood. The sterile womb paradigm has been challenged by recent reports that revealed the presence of the meconium, amniotic fluid, and placenta microbiome. This study aimed to explore the maternal origin of the microbiota of neonate meconium by using the PacBio single-molecule real-time circular consensus sequencing technology. Such technology could produce high fidelity reads of full-length 16S rRNA genes, improving the sensitivity and specificity of taxonomic profiling. It also reduced the risk of false positives. This study analyzed the full-length 16S rRNA-based microbiota of maternal samples (amniotic fluid, feces, vaginal fluid, saliva) and first-pass meconium of 39 maternal-neonate pairs. Alpha-and beta-diversity analyses revealed sample type-specific microbiota features. Most sample types were dominated by sequences representing different genera (Lactobacillus and Curvibacter in the amniotic fluid and vaginal fluid microbiota; Bacillus and Escherichia/Shigella in the meconium microbiota; Bacteroides and Faecalibacterium in the maternal fecal microbiota; Streptococcus and Prevotella in the maternal saliva microbiota). Moreover, specific operational taxonomic units (OTUs) were identified in all sample types. Dyad analysis revealed common OTUs between the meconium microbiota and microbiota of multiple maternal samples. The meconium microbiota shared more features with the amniotic fluid microbiota than the maternal fecal and vaginal microbiota. Our results strongly suggested that the meconium microbiota was seeded from multiple maternal body sites, and the amniotic fluid microbiota contributed most to the seeding of the meconium microbiota among the investigated maternal body sites.

The composition of the microbiota in the full-term fetal gut and amniotic fluid: a bovine caesarean section study

“…Complementing this with the LefSe analysis using all taxonomic levels, also found Clostridiales and Rubrobacter taxons relatively more abundant in the meconium. The microbial compositions in the bovine amniotic fluid and meconium of the corresponding neonate did not show a significant correlation, contrary to earlier studies in humans (Collado et al, 2016; He et al, 2020).…”

Microbiota in Uterine Cavity of Unexplained Recurrent Spontaneous Abortion (URSA) Patients in Early Pregnancy

“…It was previously isolated from various aqueous environments and had identified in atherosclerotic plaques (22). Curvibacter was first reported existed in the amniotic fluid and vaginal fluid microbiota of healthy pregnant women in a recent study (23). But there was no Curvibacter existed in the control group in our study, so whether it be harmful to pregnancy still need to discuss in the future.…”

Maternal IgA2 Association with Colostrum Microbiota Contributes to Bacteria Establishment During Intestinal Colonization in the Neonate.

“…We described that meconium microbiota was characterized by the Enterobacteriaceae family and Pseudomonas genera, with enrichment of Clostridium, Staphylococcus Streptococcus, which origin is still under discussion [42]. During vaginal birth, the neonate is colonized by maternal microbiota from the urogenital tract and perianal zone, characterized by Clostridium, Pseudomonas, Bi dobacterium, Lactobacillus, and Enterobacteriaceae.…”