Related Experiment Video
Updated: Mar 18, 2026
Author Spotlight: Enhancing Understanding and Treatment Strategies with the NEC-on-a-Chip Model
Published on: July 28, 2023
Cesarean section changes neonatal gut colonization
Jakob Stokholm1, Jonathan Thorsen2, Bo L Chawes2
1COPSAC, Copenhagen Prospective Studies on Asthma in Childhood, Herlev and Gentofte Hospital, University of Copenhagen, Copenhagen, Denmark; Department of Pediatrics, Naestved Hospital, Naestved, Denmark.
Insights
Cesarean section birth alters infant gut bacteria initially, but these changes normalize within a year. This early gut microbiome shift may link C-section delivery to immune diseases.
Area of Science:
- Microbiome research
- Pediatric immunology
- Epidemiology
Background:
- Cesarean section delivery is linked to increased childhood immune-mediated diseases.
- Early bacterial colonization is crucial for immune system development.
Purpose of the Study:
- To investigate how delivery method influences gut and airway bacterial colonization in infants.
- To analyze these colonization patterns within the first year of life.
Main Methods:
- Analysis of fecal and airway samples from 700 infants in the COPSAC2010 birth cohort.
- Bacterial culture from samples collected at multiple time points (1 week, 1 month, 1 year).
- Collection of data on delivery method, antibiotics, and lifestyle factors.
Main Results:
- Cesarean section was associated with specific gut bacteria (e.g., Citrobacter, Clostridium, Klebsiella) at 1 week, while natural birth was linked to E. coli.
- These delivery-related gut colonization differences diminished by 1 month and were absent by 1 year.
- No significant impact of birth method on initial airway microbiota was observed.
Conclusions:
- Cesarean section delivery impacts early neonatal gut colonization but not airway colonization.
- Gut microbiome differences normalize within the first year of life.
- Early microbial disruptions may suggest a link between cesarean birth and immune-mediated diseases.
Background:
Delivery by means of cesarean section has been associated with increased risk of childhood immune-mediated diseases, suggesting a role of early bacterial colonization patterns for immune maturation.
Objective:
We sought to describe the influence of delivery method on gut and airway colonization patterns in the first year of life in the Copenhagen Prospective Studies on Asthma in Childhood2010 (COPSAC2010) birth cohort.
Methods:
Seven hundred children from the COPSAC2010 birth cohort participated in this analysis. Fecal samples were collected at age 1 week, 1 month, and 1 year, and hypopharyngeal aspirates were collected at age 1 week, 1 month, and 3 months and cultured for bacteria. Detailed information on delivery method, intrapartum antibiotics, and lifestyle factors was obtained by personal interviews.
Results:
Seventy-eight percent of the children were born by means of natural delivery, 12% by means of emergency cesarean section, and 9% by means of elective cesarean section. Birth by means of cesarean section was significantly associated with colonization of the intestinal tract by Citrobacter freundii, Clostridium species, Enterobacter cloacae, Enterococcus faecalis, Klebsiella oxytoca, Klebsiella pneumoniae, and Staphylococcus aureus at age 1 week, whereas colonization by Escherichia coli was associated with natural birth. At age 1 month, these differences were less prominent, and at age 1 year, they were not apparent, which was confirmed by means of multivariate data-driven partial least squares analyses. The initial airway microbiota was unaffected by birth method.
Conclusion:
Delivery by means of cesarean section was associated with early colonization patterns of the neonatal gut but not of the airways. The differences normalized within the first year of life. We speculate that microbial derangements, as indicated in our study, can demonstrate a possible link between delivery by means of cesarean section and immune-mediated disease.
