The Microbiome and the Midwife

Editor’s note: This article first appeared in Midwifery Today, Issue 120, Winter 2016.
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The microbiome is a virtual swarm of micro-organisms that live in, on, and around the human body. The Human Microbiome Project, launched by the National Institutes of Health (NIH) in 2008, was a five-year project which analyzed the genetic code of the microbes living in and on the human body, with the ultimate goal of finding how changes in the human microbiome are associated with health and disease. Despite the generation of massive amounts of data, this issue is currently not well understood.

Before the microbiome project, bacteria were generally thought to be pathogenic, although it was known that there were also commensal bacteria: those harbored in the human body without causing harm. Now we know that the majority of micro-organisms in our bodies are actually beneficial. In fact, we could not live without them. They help digest nutrients, synthesize vitamins, support the immune system and help prevent the overgrowth of potential pathogens.

One big surprise is about bacteria in the uterus. In midwifery and obstetrics, we have traditionally been taught that the womb was a safe and sterile environment for the baby to grow in, and that the first introduction to bacteria occurs during passage through the vagina, or from the surfaces of the hospital resuscitation unit and the gloved hands of the personnel who give the cesarean baby his/her initial care.

In 2012, Kjersti Aagard and her colleagues at Baylor College of Medicine and Texas Children’s Hospital found that while the vaginal flora change during pregnancy, the microbial make-up of newborn baby does not resemble that of the vagina. The pregnant vagina harbors about 80% lactobacillus, creating a mildly acidic environment which discourages the growth of pathogenic bacteria. The newborns they studied harbored some lactobacillus with a variety of other organisms (Grens 2014).

They proceeded to study the bacteria on placentas, sampled immediately after birth. The bacteria resembled the inhabitants of the mother’s mouth more than any other body site, not that of the vagina. Further testing showed the greatest similarity with bacteria found in the gut and the mouth (Ibid.).

Aagard concludes, “The placental microbiome likely represents a baby’s first meeting with the microbial world. The birthing process, then, would be the second stop on a tour of the maternal microbiome. Once on the outside, a baby’s first embrace with his mother is really a group hug with her skin microbiome. And then there’s breast milk, which for many decades was also considered sterile, but which is in fact a creamy bacterial soup” (Grens 2014, 1).

Regarding the microbiome of breast milk, there is a large and complex body of research, linking to data on the salivary microbiome and the gut microbiome, which has a profound effect on the immune system. The breast milk microbiome is variable, the basic components being lactobacillus and other probiotics. The research seems to point to a single conclusion: Breast is best for the health and optimal growth of the newborn.

While we as midwives, doulas, and doctors follow this fascinating ongoing research into the microbiome, how can we use what we have learned so far to promote optimum health for mothers and babies?

As much as possible, keep mother and baby together. Don’t bathe the baby in the early hours; just wipe off sticky meconium or blood with a moist cloth. Place him skin-to-skin with his mother, and encourage early breastfeeding. Evaluate neonatal procedures that may routinely involve separation from the mother. Baby’s blood sugar can be checked in the mother’s arms. No need to move him/her to a procedure room.

Strive for a clean delivery. Don’t introduce outside bacteria to mom and baby unnecessarily. Use good hygiene when moving from one patient to another, or from a public area into mother and baby’s private area.

Delayed cutting of the cord can prevent unnecessary separation of mother and baby, and there are many other possible benefits.

Encourage your hospital to provide early contact of mother and baby as the surgeon completes the final phases of cesarean section. Many hospitals have made this change and baby can be skin to skin with the mother as the surgical team closes. There are emotional benefits to mother and baby as well as the benefits of giving the newborn his natural, complementary microbiome.

Encourage your local neonatal intensive care units to allow maximum contact between mother and baby, then work to develop services so that new mothers can be safe and comfortable while they are spending time with their sick or premature baby. Providing a place for new mothers to lie down and rest can greatly enhance their recovery.
Avoid unnecessary antibiotic use. Antibiotics alter the microbiome.

Promote breastfeeding.

Promote the development of breast milk banks, but remember that the mother’s own breast milk is especially formulated to benefit her own baby. Donor breast milk is the best substitute for the mother’s own breast milk.

Educate families about the microbiome and the benefit to baby of inheriting an intact microbiome which uniquely suits his or her genetic and cultural heritage. You can probably think of more practices which will encourage the passing of a healthy microbiome between generations. It is interesting how these seem to correlate with basic, good midwifery care.

Happy birthing, everyone!


About Author: Marion Toepke McLean

Marion Toepke McLean, CNM, attended her first birth as primary midwife in August 1971. She received her nursing degree from Pacific Lutheran University in 1966 and her midwifery and family nurse practitioner degree from Frontier Nursing Service in 1974. From 1976 through 2001 she did home, clinic and hospital births, while also working as a family nurse practitioner. In 1980 she taught a year-long program for local midwives, returning to Frontier Nursing Service to teach during the summer. She had a homebirth practice until 1985, when she went to work at the Nurse-Midwifery Birthing Service, a freestanding birth center. In June 2000 she completed a BA in International Studies at the University of Oregon, with concentrated studies on Mexico. Since 2002 she has worked in a reproductive health clinic and attended an occasional homebirth. She lives in Eugene, Oregon, and is a contributing editor to Midwifery Today.

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