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Maternal antenatal treatments influence initial oral microbial acquisition in preterm infants

Karen D Hendricks-Muñoz1, Guillermo Perez-Perez, Jie Xu

  • 1Division of Neonatal Medicine, Department of Pediatrics, Virginia Commonwealth University School of Medicine, Richmond, VA 23228, USA. hendrk01@gmail.com

American Journal of Perinatology
|July 21, 2012
PubMed

Insights

Maternal antenatal treatments significantly impact early oral microbial acquisition in preterm infants. Steroid exposure, with or without antibiotics, increased bacterial density and altered species composition, affecting gut bacteria establishment.

Area of Science:

  • Microbiology
  • Neonatology
  • Pediatric Research

Background:

  • The early establishment of the gut microbiome is crucial for infant health.
  • Preterm infants are vulnerable to microbial dysbiosis due to various factors, including medical interventions.
  • Understanding the impact of maternal treatments on infant microbial colonization is essential for optimizing neonatal care.

Purpose of the Study:

  • To investigate the association between maternal antenatal therapy and the initial oral microbial acquisition in preterm infants.
  • To analyze the colonization patterns of key gut bacteria, including Firmicutes, Bacteroidetes, Lactobacillus, Bifidobacterium, and Bacteroides species, in relation to maternal treatments.

Main Methods:

  • Oral samples were collected from preterm infants (n=65, <34 weeks gestational age) within 24 hours of birth.
  • Real-time 16S rRNA quantitative polymerase chain reaction with group-specific primers was used for microbial analysis.
  • Statistical analyses, including ANOVA and logistic regression, evaluated the effect of antenatal exposures.

Main Results:

  • Infants unexposed to antenatal treatment showed minimal Firmicutes, primarily Lactobacillus species.
  • Antibiotic exposure resulted in significantly lower total bacterial density and altered proportions of Firmicutes, Bacteroidetes, and Bacteroides.
  • Steroid exposure, alone or with antibiotics, led to an eightfold increase in total bacterial density, with a notable decrease in Lactobacillus and an increase in Bacteroides species. Bifidobacterium was undetectable across all groups.

Conclusions:

  • Maternal antenatal treatments, including antibiotics and steroids, significantly influence the early oral microbial acquisition in preterm infants.
  • These early microbial colonization patterns are critical for the establishment of gut commensal bacteria.
  • The findings highlight the need to consider the impact of maternal medical interventions on the developing infant microbiome.
Abstract

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