Gastrointestinal consequences of cesarean section birth: A systematic review of short- and long-term effects in infancy and beyond

Table 11 Cesarean section and risk of inflammatory bowel disease

Ref.	Country	Sample size	Follow-up duration	Association with IBD	Key notes/modifiable factors	Risk of bias
Bager et al[52], 2012	Denmark	2.1 million	Up to 35 years	↑ IBD (IRR: 1.29 for < 15 years)	Adjusted for family history	Low (large population, long-term, adjusted)
Andersen et al[53], 2020	Denmark	2.7 million	Up to 40 years	↑ IBD and autoimmune diseases	Risk with both elective/emergency C-section	Low (excellent registry data, confounder control)
Hellsing et al[54], 2022	Sweden	1.1 million	17 years	↑ Crohn’s (HR: 1.14)	No effect on UC	Low (well-stratified outcomes, good adjustment)
Zamstein et al[55], 2022	Israel	7337 breech births	18 years	↑ IBD hospitalizations (aHR: 3.18)	Breech delivery as key variable	Moderate (small subgroup, well-controlled)
Malmborg et al[56], 2012	Sweden	> 16000	Not specified	↑ Pediatric Crohn's (boys, OR: 1.25)	Elective C-section more strongly associated	Moderate (good design, duration unclear)
Ponsonby et al[57], 2009	Australia	Not specified	Up to 16 years	↑ Crohn's disease with elective C-section	Trend noted over time	Moderate (ecological component, unclear sample)
Bernstein et al[58], 2016	Canada	12159	Approximately 20 years	No association	Controlled for siblings, urban/rural	Low (sibling matched, good design)
Burnett et al[59], 2020	Canada	262729	Approximately 25 years	No association	Two independent cohorts analyzed	Low (large sample, replication)
Burgess et al[60], 2022	Scotland	2 million	16 years	No association	Controlled for feeding, GA, mode	Low (robust dataset, adjusted)
Sonntag et al[61], 2007	Germany	1859	Retrospective	No association	Preterm birth more influential	Moderate (small sample, retrospective)
Soullane et al[62], 2021	Canada	934873	7.4 years	No IBD association	Pediatric cohort focus	Low (strong national data, pediatric angle)

C-section: Cesarean section; HR: Hazard ratio; IBD: Inflammatory bowel disease; UC: Ulcerative colitis; IRR: Incidence rate ratio; OR: Odds ratio. Clinical Pearls 5: Evidence suggests a modest association between C-section—predominantly elective C-section—and an increased long-term risk of Crohn’s disease. At the same time, no consistent link has been found with ulcerative colitis. Geographic and genetic factors, as well as early-life gut dysbiosis, may contribute to this risk. However, findings are mixed, and Cesarean delivery alone is not considered a definitive risk factor for inflammatory bowel disease.