Paper - Review

DOI: 10.1038/s41564-021-00904-0

Abstract

Microbial colonization
← of the human intestine
→ impacts → 1⃣ host metabolism 2⃣ host immunity

❓: exactly when colonization occurs?

❗: many studies
→ have reported → bacterial DNA
← in first-pass meconium samples
❓: these samples → are collected hours - days
← after birth

⁉: whether bacteria → could be detected ← in meconium
← before birth

Feta meconium
→ was collected ← by rectal swab
← during elective breech caesarean delivers ← 1⃣ without labour 2⃣ before antibiotics
→ compared → to 1⃣ technical & procedural controls 2⃣ first-pass meconium 3⃣ infant stool

No microbial signal distinct
← from negative controls
→ was detected ← in fetal meconium
← by 16S ribosomal RNA gene sequencing

Positive 1⃣ aerobic 2⃣ anaerobic → were identified
← as likely skin contaminants
← not detected ← by sequencing ← in most samples

∴ Fetal gut colonization ← of healthy term infants
→ does not occur ← before birth

∴ Microbial profiles ← of neonatal meconium
→ reflect populations ← acquired during & after birth

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