The Microbiome at Birth

We all now know that there are trillions of bacteria in and on our bodies that are vital for day to day function. They are present in our gut, on our skin, and in our mouths. Our microbiome consists of all bacteria and microbes present in our bodies, and it plays a crucial role in maintaining our health. They help digest food, protect us against harmful bacteria, produce necessary vitamins, and even help with the development and maturation of our immune system. This ecosystem of bacteria within us is so important that some autoimmune diseases have been associated with the dysfunction of the microbiome.


The first month of life is a critical time for our immune and intestinal development, and the constitution of our microbiome is influenced by this critical time window. Initial colonizing bacterial species help set the stage for future development of the microbiome.


This initial colonization starts at birth. In a vaginal birth, maternal bacteria are transferred to the newborn, and this helps provide the baby with its initial microbiome. In Cesarean sections, however, babies do not receive that same exposure to bacteria. A recent study found that babies born from c-sections had different microbiomes than those born vaginally.   This has led to many in the lay community to argue that cesareans are harmful to neonatal development and to suggest a practice known as vaginal seeding or microbirthing.


As with all things healthcare related, recognizing there’s an effect from cesarean sections on the microbiome does not necessarily imply an actual clinical effect on the development of the newborn.  It also does not clarify what the best way to correct that difference is—should there even be a clinically significant effect.  We also know, that if there are actual effects from an intervention (if vaginal seeding does change the outcome for baby), we need to know if those effects are good or bad if there are side effects, and what major risks the intervention may entail.  Currently, the American College of Obstetrics and Gynecology (ACOG), does NOT recommend vaginal seeding unless being done in the context of a clinical study. There is a very real concern around inadvertently passing maternal infections like gonorrhea, chlamydia, and the herpes virus to newborns by this practice.  In the setting of known risks and no known benefits, it’s important to wait for ongoing studies to guide us in best practices.


Also important to note, after solid foods are introduced, any differences in infant’s microbiomes disappears.  In an extensive review of the known literature around the neonatal microbiome, Australian physicians concluded that any vaginal seeding outside of a study should be stopped until efficacy and safety can be established.


El Camino Women’s Medical Group offers the latest Minimally Invasive Solutions for gynecologic problems.   Drs. Amy TengErika Balassiano, and Pooja Gupta, all members of AAGL (American Association of Gynecologic Laparoscopy) are highly trained and experienced in the field of Minimally Invasive Gynecologic Surgery.   Dr. Erika Balassiano has also completed a Minimally Invasive Gynecologic Surgery Fellowship, under the supervision of world-renowned Dr. Camran Nezhat.


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