How the 'Microbiome' Affects Your Baby's Birth and Health

mother kissing baby's feet
A mother kisses her newborn baby.

The hottest topic in maternity care today is the microbiome and how it is affected by birth practices and how it, in turn, affects the infant for many years. The human “microbiome” refers to the 100 trillion microorganisms (bacteria, viruses, fungi) that live inside and on our bodies -- in the gut, mouth, skin, genito-urinary tract and even in breastmilk. Our health is determined to a great extent by the balance of helpful and harmful microbes.

The microbiome is normally transferred from mother to baby via the placenta during pregnancy; the vaginal canal during birth; and the mother’s skin, breastmilk, and lips in the hours, days and weeks after birth. The microbes and their genetic material play an essential role in the child’s health, development, and metabolism.

However, disruption in the transfer of the microbiome in the perinatal period due to changes in the way  pregnancy and birth are managed in the hospital have led to the increase in many diseases, such as allergies, asthma, diabetes, gastrointestinal diseases, obesity, autoimmune disorders, and some mental disorders. Until the past few years, the connection between the altered microbiome and poor health was virtually unknown. With newer technologies that allow for the study of microbes that were previously impossible to study, these connections are beginning to be discovered.

For example, cesarean delivery prevents the acquisition of the mother’s beneficial vaginal microbiome during birth; instead the infant is colonized with the hospital microbiome, which contains harmful and virulent microbes. Antibiotics, widely used for the mother during pregnancy and birth and for the infant afterwards, destroy helpful microbes. Wrapping the newly born baby in blankets and placing her in an incubator means the baby has no chance to acquire the skin microbiome of the mother, through direct contact, including skin to skin holding, licking and nuzzling. Instead the baby is exposed to the hospital microbiome via the blankets and the handling by the nurse. Infant formula deprives the baby of the rich breastmilk microbiome, and impairs the normal development of the newborn’s immune system and maturation of the baby’s gut microbiome.

These are just a few examples of how the human microbiome is altered right from birth. There is urgent need to take this into consideration as we consider risks and benefits of today’s common maternity care practices. To learn more, watch this animated introduction to the microbiome by NPR.

By Penny Simkin, PT, CCE, CD(DONA), Senior Instructor at Simkin Center for Allied Birth Vocations at Bastyr University, physical therapist, certified childbirth educator, internationally certified birth doula, DONA International birth doula trainer and DONA International founder and mentor.