Effect of Cesarean Delivery on Long-term Risk of Small Bowel Obstruction.

Objective: To evaluate the association of cesarean deliveries on the incidence of small bowel obstruction.

Methods: We formed a population-based cohort of all women with a first live birth between 1998 and 2007 using the U.K. Clinical Practice Research Datalink. Women were followed until 2015, the occurrence of a small bowel obstruction, or loss to follow-up. Cesarean delivery was identified from the Hospital Episode Statistics and small bowel obstruction events were identified using the Classification of Interventions and Procedures and International Classification of Diseases, 10th Revision codes. Cox proportional hazard models, with cesarean delivery defined as a time-dependent exposure, estimated the adjusted hazard ratios and 95% CIs of small bowel obstruction associated with cesarean delivery.

Results: The cohort included 81,480 women with a median follow-up of 8.0 years (range 6 months to 16.6 years), during which 575 new small bowel obstructions occurred (incidence 9.1/10,000 person-years). Risk of small bowel obstruction was higher among women with a cesarean delivery compared with women without (16.3 vs 6.4 patients/10,000 person-years, odds ratio [OR] 2.54, 95% CI 2.15-3.00). Increasing number of cesarean deliveries was associated with an increasing risk of small bowel obstruction (OR 1.61, 95% CI 1.46-1.78, per additional cesarean delivery). Repeated small bowel obstructions were more common among women with a cesarean delivery and the association remained when restricting to small bowel obstruction requiring surgical management.

Conclusion: Although rare, small bowel obstructions are increased among women who have undergone a cesarean delivery. With increasing rates of cesarean deliveries worldwide, small bowel obstructions and related morbidities may become a more prevalent women's health concern.