COVID-19 in the Neonatal Period in a Reference Maternity for High-Risk Pregnancy: A Hospital-Based Case-Control Study

COVID-19 in newborns presents a multifaceted clinical spectrum, with the potential for severe outcomes. This study aimed to evaluate the clinical evolution and hospital outcomes of neonates with a molecular diagnosis of COVID-19. A case-control study was conducted in a public referral maternity hospital for high-risk pregnancies. Two controls were selected for each case, matched by sex and gestational age. Variables related to birth data, symptoms, and clinical progression were collected from medical records and analyzed statistically, with crude and adjusted relative risks calculated using Poisson regression with robust standard errors. A total of 25 neonates with confirmed SARS-CoV-2 infection were identified among 875 newborns. Compared with controls, infected neonates had a longer hospital stay (median of 19 days vs. 8 days; p < 0.001) and higher readmission rates (16% vs. 0%; p = 0.03). After adjusting for potential confounders, COVID-19 infection was associated with a 2.41-fold higher risk of neonatal death (95% CI: 1.24–4.67; p = 0.009). No evidence of vertical transmission was found. These findings suggest that neonates with COVID-19 may experience longer hospitalizations and an adjusted higher risk of mortality, emphasizing the need for vigilant surveillance and supportive care. However, given the observational design of the study, these results indicate associations rather than causal relationships. Understanding the clinical behavior of COVID-19 in this population—characterized by inherently low immunity—and recognizing its interaction with other neonatal conditions are essential for improving hospital management and outcomes.