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Investigating prenatal and perinatal factors on meconium microbiota: a systematic review and cohort study
Jenni Turunen1,2, Mysore V Tejesvi3,4, Niko Paalanne5,6
1Research Unit of Clinical Medicine, University of Oulu, Oulu, Finland. jenni.turunen@oulu.fi.
Background:
The first-pass meconium has been suggested as a proxy for the fetal gut microbiota because it is formed in utero. This systematic review and cohort study investigated how pre- and perinatal factors influence the composition of the meconium microbiota.
Methods:
We performed the systematic review using Covidence by searching PubMed, Scopus, and Web of Science databases with the search terms "meconium microbiome" and "meconium microbiota". In the cohort study, we performed 16 S rRNA gene sequencing on 393 meconium samples and analyzed the sequencing data using QIIME2.
Results:
Our systematic review identified 69 studies exploring prenatal factors, immediate perinatal factors, and microbial composition in relation to subsequent health of infants but gave only limited comparative evidence regarding factors related to the composition of the meconium microbiota. The cohort study pointed to a low-biomass microbiota consisting of the phyla Firmicutes, Proteobacteria and Actinobacteriota and the genera Staphylococcus, Escherichia-Shigella and Lactobacillus, and indicated that immediate perinatal factors affected the composition of the meconium microbiota more than did prenatal factors.
Conclusions:
This finding supports the idea that the meconium microbiota mostly starts developing during delivery.
Impact:
It is unclear when the first-pass meconium microbiota develops, and what are the sources of the colonization. In this systematic review, we found 69 studies exploring prenatal factors, immediate perinatal factors, and microbial composition relative to subsequent health of infants, but there was no consensus on the factors affecting the meconium microbiota development. In this cohort study, immediate perinatal factors markedly affected the meconium microbiota development while prenatal factors had little effect on it. As the meconium microbiota composition was influenced by immediate perinatal factors, the present study supports the idea that the initial gut microbiota develops mainly during delivery.
Insights
The first-pass meconium microbiota composition is primarily influenced by immediate perinatal factors, not prenatal ones, suggesting gut microbial development begins during delivery.
Area of Science:
- Microbiology
- Neonatal Health
- Gut Microbiome Research
Background:
- The first-pass meconium is considered a proxy for fetal gut microbiota due to in utero formation.
- Understanding factors influencing meconium microbiota composition is crucial for infant health.
- Limited comparative evidence exists on factors affecting meconium microbiota development.
Approach:
- Systematic review of PubMed, Scopus, and Web of Science databases using keywords 'meconium microbiome' and 'meconium microbiota'.
- 16S rRNA gene sequencing of 393 meconium samples.
- QIIME2 analysis of sequencing data.
Key Points:
- Systematic review identified 69 studies but found limited consensus on factors influencing meconium microbiota.
- Cohort study revealed a low-biomass microbiota dominated by Firmicutes, Proteobacteria, Actinobacteriota, and genera like Staphylococcus, Escherichia-Shigella, and Lactobacillus.
- Immediate perinatal factors significantly impacted meconium microbiota composition, more so than prenatal factors.
Conclusions:
- Immediate perinatal factors markedly affect meconium microbiota development.
- Prenatal factors have minimal impact on meconium microbiota composition.
- The initial gut microbiota develops mainly during the delivery process.
