Natural history of inguinal hernia in neonates and infants: clinical regression and incarceration.

PURPOSE: In our institution, infants with inguinal hernias are managed with elective repair at approximately 1 year of age to reduce perioperative complications and allow for possible clinical regression. This study aimed to clarify the natural history of infantile inguinal hernia and identify factors associated with clinical regression and incarceration. METHODS: We conducted a retrospective chart review of patients diagnosed before 1 year of age between 2015 and 2023, supplemented with telephone follow-ups to confirm clinical regression. Factors associated with clinical regression were analyzed, and the time to incarceration was evaluated using a Fine-Gray competing risks model with surgery as a competing event. RESULTS: In total, 357 patients were included. Clinical regression was confirmed in 45 patients, including 33 term infants with a median follow-up period of 5.3 (IQR 3.9-8.0) years. In multivariable analysis, older age at diagnosis was independently associated with a lower likelihood of clinical regression (odds ratio: 0.65 [0.51-0.82]). Incarceration occurred in 43 patients and was associated with male sex (multivariable subdistribution hazard ratio: 2.68 [1.19-6.02]). CONCLUSION: Despite the risk of incarceration, a watchful waiting strategy may be acceptable for selected patients when careful follow-up and prompt access to care are available.