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).
From birth, gut microbiota has a major impact on the development of fetuses. The womb was thought to be a sterile environment up until recently. Probably because most scientists were men who didn’t know anything about periods. If they had asked a woman, she could’ve told them there are A LOT of bacteria, since they have to deal with it every month. Recently, research has revealed the necessity for the mother’s womb to develop the infant microbiome before birth. The mother’s womb transfers nutrients to the infant to breakdown breast milk and is important for the breakdown of toxins and drugs; vitamin synthesis; and ion absorption (1).
Gut microorganisms protect the infant from pathogenic organisms. The initial gut microbiome of infants develops in the first three years and is influenced by maternal and neonatal exposures, including mode of delivery, antibiotic exposure, and feeding patterns, diet, and stress (1). This gut colonization is imperative for the infant’s development and growth at the early stages of life. Colonization of the gut from mutualistic bacteria forms the basis of the immune system for homeostasis. This homeostasis also determines the oral tolerance for the mutualistic bacteria as well as the benign antigens that the immune system produces (1). If this homeostasis cannot be established, an imbalance of the microbiome could occur (dysbiosis) which would leave the infant vulnerable to allergies or pathogens. The main species of bacteria that colonize the infant’s gut are from the phyla Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria (1).
In the first month of life, the number of bacteria Enterococcus faecalis that colonized the infant gut microbiome varies based on hospital location and whether the infant was fed with breastmilk or formula (2). Bacterium Bacteroides-Prevotella influenced infant weight and the ponderal index, how lean someone is. There was strong causation between how an infant was fed in the first month of life and health issues later on (2). Altering the microbiota in an infant early in life can be dangerous. A large change in infant microbiota has been linked to a higher risk for necrotizing enterocolitis, a critical gut inflammation that can kill premature infants or cause permanent intestinal damage (3). Other less drastic microbiota changes have been linked to asthma or diabetes (3). Due to this research, feeding supplements such as formulas should not be given to infants considering the lack of nutrients that might cause dysbiosis and long-term negative effects on infants.
[1] Yang I, Corwin EJ, Brennan PA, Jordan S, Murphy JR, Dunlop A. 2016. The Infant Microbiome. Nursing Research 65:76–88.
[2] Obermajer T, Grabnar I, Benedik E, Tušar T, Pikel TR, Mis NF, Matijašić BB, Rogelj I. 2017. Microbes in Infant Gut Development: Placing Abundance Within Environmental, Clinical and Growth Parameters. Scientific Reports 7.
[3] DeWeerdt S. 2018. How baby’s first microbes could be crucial to future health. Nature.
