How Can I Support My Baby’s Gut After a C-Section? Here’s What the Science Says

C-sections are a critical and often life-saving part of modern obstetric care. As their use has increased, researchers have begun to better understand how birth mode influences early microbial development, particularly in the gut. These differences aren’t a reflection of anything a parent did wrong. Instead, they offer insight into how we can better support infants in the first months of life, when the microbiome and immune system are developing together.

A new clinical trial published in Pediatric Allergy and Immunology looked at whether we can actually support and restore the infant microbiome after a C-section — and what that might mean for long-term health. Let’s walk through what it found, and why it matters for your baby.

The Missing Microbes After a C-Section

The first few months of life are a critical window for immune development. And one of the biggest influences during that time? The gut microbiome.

Babies born vaginally are naturally exposed to beneficial microbes from their mother, especially Bifidobacterium, which help digest breast milk and support immune training.

Babies born via C-section, on the other hand, tend to develop a very different microbial profile:

• Lower levels of Bifidobacterium ²

• Higher levels of skin and hospital-associated bacteria³

• Reduced ability to break down human milk oligosaccharides (HMOs) ²

These early differences have real world consequences; they’ve been linked to higher risks of: atopic disease, like eczema and allergies, as shown in our own My Baby Biome study. ²

What This Study Did Differently

This study asked a simple but important question: Can we actively guide a baby’s microbiome back toward a healthier path?

Researchers followed C-section born infants (ages 0–3 months) and provided one group with a microbiome-based program, including:

• Gut microbiome testing

• Personalized recommendations

• Parent education and coaching

The other group received standard care. Over six months, they tracked both microbiome changes and health outcomes.

*Medical Disclaimer

The information provided on this blog is for educational purposes only and is not intended as medical advice, diagnosis, or treatment. Every baby is unique, and health decisions should always be made in partnership with a qualified healthcare professional. If you have questions or concerns about your child’s health, diet, or development, please consult your pediatrician or another trusted healthcare provider before making changes.

References:

1. Nieto, P. A., Nakama, C., Trachsel, J., Goad, D., Soderborg, T. K., Tan, D. S., Orlandi, A., Yuan, Q., Song, E., & Mueller, N. T. (2025). Improving immune-related health outcomes post-cesarean birth with a gut microbiome-based program: A randomized controlled trial. Pediatric Allergy and Immunology, 36(9), e70182. https://doi.org/10.1111/pai.70182.

2. Jarman, J.B., Torres, P.J., Stromberg, S. et al. Bifidobacterium deficit in United States infants drives prevalent gut dysbiosis. Commun Biol 8, 867 (2025). https://doi.org/10.1038/s42003-025-08274-7. 

3. Shao, Y., Forster, S.C., Tsaliki, E. et al. Stunted microbiota and opportunistic pathogen colonization in caesarean-section birth. Nature 574, 117–121 (2019). https://doi.org/10.1038/s41586-019-1560-1.

4. Lawson, M., et al. Breast milk-derived human milk oligosaccharides promote Bifidobacterium interactions within a single ecosystem, The ISME Journal, Volume 14, Issue 2, February 2020, Pages 635–648, https://doi.org/10.1038/s41396-019-0553-2.