Although surgery represents the only definitive treatment for congenital scoliosis, comprehensive information regarding trends in perioperative complications, particularly in the pediatric setting, is lacking. We sought to identify trends in and factors associated with perioperative complications following pediatric scoliosis surgery. In this retrospective cohort study, patients below the age of 21 years undergoing a scoliosis repair procedure were identified from the Premier Healthcare database (2006-2016). The primary outcomes of interest were any complication, cardiopulmonary complications, blood transfusions, intensive care unit (ICU) admission, length of stay (LOS), and cost of hospitalization. Trends in these outcomes over time were analyzed. Multivariable logistic regression models were run to identify factors associated with each of the perioperative outcomes. In the full cohort of 9351 scoliosis patients, 17% experienced any complication, 12% of which were cardiopulmonary in nature, 42% required blood transfusions, and 62% were admitted to the ICU. Median LOS was 5 days (interquartile range [IQR], 4-6) and median cost was $56,375 (IQR, $40,053-$76,311). Annual incidence of complications and blood transfusions as well as LOS and cost decreased significantly throughout the study period. The most consistently observed factors associated with complications were younger age, high comorbidity burden, low institutional case volume, and hospital teaching status. Although the incidence of the studied adverse outcomes in scoliosis surgery has decreased over time, this study shows it remains relatively high (17%). The associations demonstrated help clarify factors associated with complications and may be useful in guiding interventions to improve outcomes.