ImportanceSeveral studies have demonstrated a decrease in the occurrence of child abuse in the US since the start of the COVID-19 pandemic. This finding has generated concern for missed cases due to the initial lockdowns and lack of childcare resources. Determining the association of the pandemic on hospitalizations for severe forms of abuse is essential to focus preventive efforts.ObjectiveTo examine trends in abusive head trauma (AHT) before and during the COVID-19 pandemic.Design, Setting, and ParticipantsRetrospective, multicenter, repeated cross-sectional study, conducted January 1, 2016, through April 30, 2022, with data from tertiary care children’s hospitals and contributors to the Pediatric Health Information System. Data were obtained for 2380 hospitalizations of children younger than 5 years with International Classification of Diseases, Tenth Revision, Clinical Modification codes for both abuse and head trauma.Main Outcomes and MeasuresMonthly hospitalizations were analyzed using interrupted time-series analysis. Hospitalization severity (eg, intensive care unit stay) and clinical characteristics (subdural hemorrhages and retinal hemorrhages) were compared before and after the start of the pandemic.ResultsWe identified 2380 hospitalizations due to AHT (median age, 140 [IQR, 75.0-325.5] days) from 45 hospitals. The mean (SD) monthly incidence of AHT was 34.3 (5.8) before the COVID-19 pandemic compared with 25.6 (4.2) during COVID-19 (a 25.4% decrease). When the pre–COVID-19 and during COVID-19 periods were compared, there were no significant differences in severity or clinical characteristics. On interrupted time-series analysis, there was a significant decrease in the number of monthly hospitalizations (−8.1; 95% CI, −12.41 to −3.72; P < .001) in the first month of the pandemic. In the subgroup of children younger than 1 year, there was a significant decrease in monthly hospitalizations at the onset of the pandemic (−8.2; 95% CI, −12.02 to −4.43; P < .001) followed by a significant temporal increase across the COVID-19 period (P = .01).Conclusions and RelevanceThe findings of this cross-sectional study suggest there was a significant decrease in monthly hospitalizations for AHT following the start of the pandemic in March 2020. Although there was no corresponding increase in hospitalization severity, the decrease during the pandemic may have been transient, as monthly hospitalizations for children younger than 1 year increased significantly over time during COVID-19, after the initial decrease.