List and describe potential factors that the mother or the infant could be exposed to that could influence the colonization of the microbial community in the newborn infant (in positive or negative ways).
The gut microbtiota has three essential roles: protection, metabolic, and trophic. They are a barrier against pathogenic organisms. They also aid in the digestion and metabolism of breast milk for infants. Trophic functions include aiding the growth and differentiation of epithelial cells lining the gut.
During the first three years of life, the gut microbiome development is influenced by maternal and neonatal exposures. This includes mode of delivery, antibiotic exposure, and feeding patterns. Idealy, by the end of this period, the infant gut microbiome has similar diversity and composition of the adult gut.
The mode of delivery is a very important contributing factor the gut microbiota variation. When born vaginally, they have a gut microbiome that is very similar to that of their mother’s vaginal and fecal flora. Cesarean section compromises the horizontal transfer of bacteria between mother and child. The differences in the initial gut microbiota communities may have important health consequences, which can result in pathogens. There have also been cases that show infants who are separated from their mothers after birth for an extended period of time can result in a loss of colonization with the maternal skin microbiome.
Another factor that influences the gut microbiome of infants is if they receive antibiotics prior to delivery. The administration of antibiotics pre-birth has been shown to reduce the diversity of gut flora and delays the colonization of commensal flora. Although it is commonly practiced as a way to protect against the colonization of pathogen microorganisms, it can have negative consequences.
Feeding patterns of infants can also influence their gut microbiota. Formula-fed infants exhibit a more diverse flora than breast-fed infants. This diversity, however, does not always aid in health. Some studies have shown that infants colonized with C. difficile are at a higher risk of developing atopic symptoms, such as eczema, wheeze, allergic sensitization, and atopic dermatitis.
Yang I, Corwin EJ, Brennan PA, Jordan S, Murphy JR, and Dunlop A. 2016. The Infant Microbiome: Implications for Infant Health and Neurocognitive Development. Nursing research, 65(1), 76–88. doi: 10.1097/NNR.0000000000000133