Objective: evaluation of factors affecting hospitalization of children of the first month of life in a multi-disciplinary children's hospital in a metropolitan area. Material and methods. Using the continuous method, data from 267 children in the first month of life in St. Petersburg was copied from the Ariadna medical information system. Re-sults. In 2020-2022 the majority of children were treated through compulsory medical insurance (89.5-93.2%). During the year of the COVID-19 pandemic, 66.7% of patients were admitted as emergencies. More than half of the children were admitted through internal routing. In 2022, the highest hospitalization rate was in patients with certain conditions arising in the perinatal period (452.6%o) and congenital malformations (242.1%o), and the longest average duration of treatment was observed in patients with factors influencing health status population and visits to health care institutions (24.5±7.5 days), respiratory diseases (22.5±21.5 days). Most children were discharged with improvement. Conclusion. The hospitalized morbidity of children in the neonatal period is influenced by a significant number of factors, among the main ones being the location of the medical organization, the presence of a perinatal center in its structure and the COVID-19 pandemic.