Mode of Delivery and the Microbiome

Our gut is colonized by a variety of good and bad microorganisms that make up our microbiome. The microbiome has been found to play a role in our digestion, immune response, and overall health. According to Dr. Cramer, the microbiome is not fully developed until an infant is three years old. Therefore, the microbiome that I have now as an adult, is not the same as the microbiome that I had as an infant. Mechanisms that determine the make-up of our microbiome include our mode of delivery, breastfeeding exposure and diet, and antibiotic use, to name a few. It is difficult not to get overwhelmed and anxious thinking about all the ways that we may be currently harming our microbiome or worsened it in the past.

To set infants up for the most protective microbiome, I think it’s important to think about their first exposure in life: birth. Mode of delivery is one of the ways that infants acquire their microbiome and researchers have seen differences in the microbiome of infants born via vaginal delivery vs. via a cesarean delivery. In a recent study, infants who were born vaginally had a gut microbiome that resembled their mom’s whereas infants who were born via cesarean section did not. In fact, their gut microbiome was more reflective of the bacteria that was present in the hospital and they had more bacteria that had antibiotic resistance. Though microbiome differences were not as apparent by the time the infants were a couple months old, I think these initial differences in microbiome make-up could have negative implications for the infant’s future health, as they may be less susceptible to potentially necessary antibiotic treatment. In addition, research has found that cesarean section infants have a greater risk of experiencing allergies, asthma, and inflammatory bowel disease which are all tied to their immune response. On the contrary, infants who are vaginally born experience less immune-related diseases. Though these findings are worrisome, I don’t think it is a good idea to scare parents into thinking that their infant will be “unhealthy” if they are born via cesarean section. Many infants who are born this way will probably go on to lead healthy lives, but it is still important to find ways to help these infants optimize their health.

It is important to research mode of delivery and its impact on the microbiome because current rates highlight that is a popular procedure. In 2018, about 32% of live births in the United States were delivered by a cesarean delivery. This is an alarmingly large percentage, considering that the World Health Organization (WHO) only recommends that 10-15% of pregnancies within a population result in a cesarean delivery. Though a cesarean-section may save the life of the mom and/or baby and be medically-necessary in certain situations is it important that this form of delivery is not abused. This is especially pertinent since microbiome research is continuously evolving and we do not fully understand the consequences. Though it would be costly and time-consuming, future studies should try to track infants over time to see how their microbiome evolves during infancy, at least until they are three years old. This longitudinal view could give us a better picture of how microbiome development impacts child and adult health. Hopefully, as research evolves, we will find a way to easily improve and maintain a healthy microbiome.

References

Centers for Disease Control and Prevention. Cesarean Delivery Rates. 2019, https://www.cdc.gov/nchs/pressroom/sosmap/cesarean_births/cesareans.htm.

Hopkins, Mark J., et al. “Characterisation of Intestinal Bacteria in Infant Stools Using Real-Time PCR and Northern Hybridisation Analyses.” FEMS Microbiology Ecology, vol. 54, no. 1, Oxford Academic, Sept. 2005, pp. 77–85, doi:10.1016/j.femsec.2005.03.001.

Hunt, Katie. Babies Born by C-Section Have Less of Mom’s Gut Bacteria. Here’s Why That’s Important – CNN. 2019, https://www.cnn.com/2019/09/18/health/babies-gut-microbiome-birth-vaginal-c-section-intl/index.html.

Koenig, Jeremy E., et al. “Succession of Microbial Consortia in the Developing Infant Gut Microbiome.” Proceedings of the National Academy of Sciences of the United States of America, vol. 108, no. SUPPL. 1, National Academy of Sciences, Mar. 2011, pp. 4578–85, doi:10.1073/pnas.1000081107.

Prakash, Satya, et al. “Gut Microbiota: Next Frontier in Understanding Human Health and Development of Biotherapeutics.” Biologics: Targets and Therapy, Dove Medical Press Ltd., July 2011, p. 71, doi:10.2147/btt.s19099.

Turroni, Francesca, et al. “The Infant Gut Microbiome as a Microbial Organ Influencing Host Well-Being.” Italian Journal of Pediatrics, vol. 46, no. 1, Dec. 2020, p. 16, doi:10.1186/s13052-020-0781-0.

World Health Organization. Caesarean Sections Should Only Be Performed When Medically Necessary. 2015, https://www.who.int/mediacentre/news/releases/2015/caesarean-sections/en/.