Meconium microbiota types dominated by lactic acid or enteric bacteria are differentially associated with maternal

M J Gosalbes1, S Llop, Y Vallès

  • 1Unidad Mixta de Investigación en Genómica y Salud-Centro Superior de Investigación en Salud Pública Generalitat Valenciana, Institut Cavanilles de Biodiversitat i Biologia Evolutiva Universitat de València, Valencia, Spain.

Abstract

Insights

The newborn

Area of Science:

  • Microbiology
  • Neonatal Health
  • Gut Microbiome

Background:

  • Culture-dependent methods indicate meconium is not sterile, but its bacterial diversity requires advanced molecular characterization.
  • Understanding the meconium microbiota is crucial for neonatal health and early life gut colonization.

Purpose of the Study:

  • To molecularly characterize the meconium microbiota in term infants.
  • To determine if meconium microbiota contributes to the infant's gastrointestinal tract microbiota.
  • To evaluate associations between meconium microbiota and maternal lifestyle or infant atopy-related conditions.

Main Methods:

  • High-throughput pyrosequencing of the 16S rRNA gene was used to analyze meconium microbiota in 20 term newborns.
  • Comparison with maternal pre-delivery fecal samples, infant fecal samples up to seven months, and independent vaginal/skin microbiota studies.
  • Statistical evaluation of meconium microbiota types based on taxonomic composition, abundance, and associated factors.

Main Results:

  • Meconium microbiota differs from adult feces, vagina, and skin, but resembles that of young infants.
  • Two distinct meconium microbiota types were identified: one less diverse, dominated by enteric bacteria, linked to maternal atopic eczema; the other dominated by lactic acid bacteria, linked to infant respiratory problems.

Conclusions:

  • Meconium microbiota likely originates in utero and plays a role in initial gut colonization.
  • Maternal factors appear to influence meconium bacterial composition, potentially impacting infant health outcomes.
  • Further research with larger cohorts is warranted to confirm these associations and their clinical implications.

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