Abstract
OBJECTIVE: To assess COVID-19 association with newborn critical care outcomes, including nursery level of care and ventilation, during three time periods: Pre-delta (May 2020-June 2021), Delta (July-November 2021), and Omicron (December 2021-February 2022). STUDY DESIGN: In a retrospective cohort of newborns born May 2020-February 2022 using the Premier Healthcare Database, we classified COVID-19 status and critical care using International Classification of Diseases 10th Revision and Current Procedural Terminology codes, laboratory data, and billing records and assessed for variation during three time periods. RESULTS: Of 1,388,712 newborns, 0.06% had COVID-19 during the birth hospitalization (Pre-delta period: 0.03%; Delta: 0.07%; Omicron: 0.21%). Among newborns with COVID-19, the risks for admission to a higher-level nursery and for invasive or non-invasive ventilation were lower in the Omicron period compared to Pre-delta and Delta periods. CONCLUSION: From May 2020-February 2022, COVID-19 in newborns was rare and cases were less severe during the period of Omicron predominance.