Maternal and infant factors that shape neonatal gut colonization by bacteria

ABSTRACT

Introduction

Early life is a critical developmental window coinciding with the establishment of a community of neonatal gut microbes which are vitally important for immune development. The composition of this microbial community is affected by multiple factors.

Areas covered

The effect of pre-pregnancy and pregnancy maternal health, maternal nutrition, pregnancy disorders such as gestational diabetes, maternal antibiotic usage, delivery mode, infant feeding, and infant antibiotic usage on gut microbial composition are outlined along with the potential impact of associated microbiota differences on infant health.

Expert opinion

Recent developments in understanding what shapes our microbiota indicates that the greatest impact on infant gut microbiota composition during the first year of life is seen with the mode of delivery, infant diet, and infant antibiotic usage. Current data is insufficient to fully establish the role of apparently less important factors such as maternal health on microbiota development although their impact is likely smaller. Technological advances will allow for improved understanding of underlying mechanisms by which specific microbes impact on infant health, which in time will enable full appreciation of the role of the gut microbiota in early life development.

KEYWORDS:

• Microbiome
• microbiota
• pregnancy
• infant
• breastmilk
• delivery
• antibiotics
• gut microbiota
• infant health

Article highlights

• Early life microbiota composition is influenced by maternal and infant factors

• Microbial colonization primarily occurs after birth but there may be some colonization in utero, although this remains highly controversial.

• Maternal factors during pregnancy that can affect the infant microbiota include maternal diet, weight, gestational weight gain, and antibiotic usage but overall, their impact is low in comparison to that of birth mode, infant diet, and antibiotic treatment.

• Microbes are passed from mother to infant during and after birth. The major contributor to the infant microbiota appears to be the maternal gut microbiota and environmental microbes whereas vaginal microbes are present in lower abundance.

• Delivery mode, breastfeeding, and intrapartum and early life antibiotic treatment have the largest effects on microbial composition in early life.

Altered microbiota composition may lead to increased risk or asthma, eczema, and allergies.

Declaration of interest

E F Murphy is Technical Director at Alimentary Health Group. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose

Additional information

Funding

This paper was funded by a research grant from Science Foundation Ireland under [Grant No. 12/RC/2273 and 16/SP/3827] and by a research grant from Alimentary Health Ltd. D van Sinderen, R Saldova, P D.Cotter, F M. McAuliffe and R S Gallardo are all supported by this grant. I J O’Neill has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. [754535].