BackgroundIntra-abdominal adhesions can lead to adhesive small bowel obstruction (ASBO). The incidence of ASBO is higher in paediatric surgery than in adult surgery. However, ASBO related complications, economic burden and clear management guidelines in the treatment of ASBO are lacking. The aims of this study were to investigate underlying diagnoses, treatments, complications and costs in paediatric ASBO. MethodAn observational retrospective study in children 0–15 years, hospitalised for ASBO during 2000–2020. Data were extracted from the medical records. Complications were classified based on Clavien Dindo Classification of Surgical Complications. Descriptive statistics were presented as median, continuous variables and categorical variables summarised with frequencies. Time to ASBO was presented as a Kaplan–Meier estimate. ResultsIn total, 101 patients with 137 episodes of ASBO were included whereof 58.4% underwent first (index) surgery during the neonatal period. Median follow-up was 11.3 (0.6–19) years and median time to the first ASBO was 3.76 months (95%CI 2.23–12.02). The most common diagnoses at index surgery were necrotising enterocolitis, duodenal obstruction and primary ASBO. In 86.6% of the patients, first ASBO did not resolve with conservative treatment and a laparotomy was needed. Postoperative complications were found in 52%. Median cost for one episode of acute ASBO was 36 236 USD (1629–236 159). ConclusionNeonatal surgery was the dominating cause of ASBO and surgical intervention the most common treatment with a high frequency of postoperative complications and significant healthcare costs. Future studies are needed to develop safe management guidelines for the treatment of paediatric ASBO. Levels of EvidenceIII.