good bacteria

Your Microbiome

The Human Microbiome is the collection of bacteria, viruses, fungi, and other organisms that live in and on the body. The largest of these is found in the GUT (31). Trillions of these microorganisms live within us, outnumbering our human cells by 10:1 and our genes by 100:1 (31). The microbiome is so distinctive to each person that even identical twins have their own unique collection of bacteria (32). These bacteria have a direct link to health and disease. A happy and healthy collection of bacteria leads to optimal health.

Disruption of this balance may lead to diseases including:

  • allergies,
  • asthma,
  • diabetes,
  • bowel disorders,
  • obesity,
  • some cancers,
  • Alzheimer’s,
  • Parkinson’s and
  • Autism (because of a gut-brain connection) (31).

What shapes the microbiome?

Health, lifestyle and age influence the microbiome. It is forever changing in response to different periods of life. A woman’s gut and vaginal microbes change during each trimester, supporting the growth and development of the unborn baby (33).

Previously, it was thought the uterus was a sterile environment. However recent studies have shown that a mother’s microbes cross the placenta (31). As the baby passes through the birth canal, vaginal microbes are also transferred. These bacteria initiate the baby’s microbiome and kick-start their immune system. This colony will then continue to evolve and adapt during the child’s lifespan (31).

During vaginal birth, the mother’s vaginal and faecal (poo) microbes colonize the baby. In contrast, a caesarean birth exposes the baby to microbes from maternal skin and the hospital environment (33). Babies born vaginally have a more diverse and dense variety of microbes than those born by caesarean section (34).

Since the mother’s bacteria is the source of her baby’s microbiome, women should begin pregnancy with a healthy balance and maintain it.

Seeding the microbiome

If your baby is born by caesarean, you can expose the baby to vaginal bacteria by ‘seeding’ (or swabbing). Research is being conducted into the use of vaginal swabs to colonize babies that are born via caesarean section. Studies have found swabbed babies had twice as much maternal bacteria as babies who were born via caesarean birth but not swabbed (35). “Seeding” the newborn using vaginal swabs has been open to much debate and further research is necessary.

The protocol researchers are currently using is:

  • Take a piece of gauze soaked in sterile normal saline.
  • Fold it up like a tampon with lots of surface area and insert into the mother’s vagina
  • Leave for one hour, remove just prior to surgery and keep in a sterile container
  • Immediately after birth apply the swab to the baby’s mouth, face, then the rest of the body (35).

The human microbiome is essential to our health. Maintaining a balanced microbiome during pregnancy, birth and breastfeeding may have a long-term impact on health and disease. While some of these tips are supported by scientific research, not all have been adequately researched. More research is needed to explore how best to support healthy colonization and maintenance of the microbiome during this key period.

Supporting your good bacteria

  • Enjoy a well-balanced diet, minimise processed foods and toxins.
  • Eat fermented foods (natural yoghurts, kefir, sauerkraut, other fermented vegetables kombucha, etc.…).
  • Consume prebiotic foods (high in oligosaccharides). These can also help feed the microbiome (onion, garlic, legumes, starchy vegetables)
  • Take daily probiotic supplements to increase healthy bacteria.
  • Avoid unnecessary antibiotic use. If you need antibiotics, consider probiotic support.
  • If antibiotic use is necessary, continue to take probiotics
  • Minimise stress whenever possible
  • Stop smoking
  • Birth vaginally when possible
  • Straight after birth, place baby to mother’s chest for unhurried skin-to-skin time.
  • Feed baby only breastmilk for as long as possible. Breastmilk exposes the baby to more microbes that aid digestion.
  • Wait 24 hours after birth to bath the baby so the skin microbiome can be absorbed.

Kelly Padrão West (BMid, BHSc Nut.Med), Registered Midwife & Nutritionist
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