Where do Babies Microflora come from?

Your body is covered, inside and out, with trillions of microbes whose role is so vital to your survival that the entirety of them (called your microflora) is now widely regarded as “the forgotten organ”. Being that the microflora by definition consists of foreign microbes you might wonder how you came by yours? Where did these trillions of diverse microbes come from? And most importantly how do you ensure you get a good one?

baby and mother sloth microflora

Sloths have VERY impressive microflora

Like your mitochondria, the microflora is a gift from your mother. With a babies first microflora introduced in three steps–in the womb, during birth, and while breastfeeding.

Until recently, it was widely believed that the fetus develops in a sterile environment, free from all microbes. Yet, recent findings show commensal (non-harmful) bacteria are present in the amniotic sac–the protective sac in which the baby develops. [Not to be confused with Chorioamnionitis, which is a dangerous infection of the amniotic sac by harmful bacteria.]

Stages of Microflora Inheritance

During pregnancy, the mother’s microbiota changes to more closely resemble what is seen in newborns. With the mother’s bacteria migrating from all over the body to the baby. Variations in the inherited microbiome arise based on the mother’s microbiome, diet, health, and antibiotic usage. Once a microbiome is inherited, it is difficult to alter, and could influence the metabolism and immune system of the child for years.

During birth, as a baby passes through the vaginal canal, he or she is exposed to several key types of bacteria that prepare the gastrointestinal tract to be colonized by other essential bacteria later on. Babies born by c-section are not exposed to these beneficial microbes, and lack the benefits that are associated with natural birth; and put the baby at a significantly higher risk for asthma, type-1 diabetes, celiac disease, and obesity. Luckily, now that we know this we are able to create probiotic cocktails so that babies born by c-section are exposed to these beneficial microbes.

Microflora as an Infant to Adulthoodemi13318-fig-0001

In the months after birth, breastfeeding provides prebiotics and commensal microbes to the infant. which regulate mucosal barrier function, promote healthy immunological and inflammatory responses, and prevent harmful pathogens from colonizing the gastrointestinal tract. Using baby formula instead can have major implications on the child’s microbiome, and overall well-being by not providing infants with these prebiotics and commensal microbes. Not breastfeeding a child has been correlated to increased infectious morbidity by pneumonia and gastroenteritis, higher risk of childhood obesity, diabetes, and sudden infant death syndrome (SIDS). This isn’t wholly due to the microbial effects of breastfeeding, however. Breast milk also provides the infant with an immune system while the baby’s own immune system is developing.

Between six months and a year old when a child starts eating food (and sometimes dirt) their microbiota becomes even more diverse and will begin to resemble what it will look like as an adult. Throughout your life, the makeup of your microbiome will vary based on environment, diet, lifestyle, genetics, and antibiotic usage. However, the microbes obtained in the womb, during birth, and early diet lay the foundation for the microbiome, the immune system, metabolism, and overall health of a person.  

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