Epidemiological investigation of fetal laterality disorders in multiple hospitals in coastal Southeastern China before and after the COVID-19 pandemic (2017-2024).

Background: Fetal laterality disorders are rare congenital anomalies including situs inversus, partial heterotaxy, and heterotaxy syndrome. They are associated with increased risks of conditions such as congenital heart defects and primary ciliary dyskinesia. Recent studies have suggested a rise in the incidence of situs inversus following the COVID-19 pandemic. The purpose of this study is to investigate trends in the incidence of fetal laterality disorders before and after the COVID-19 pandemic. Materials and methods: This study included all pregnant women who underwent fetal ultrasound examinations between January 1, 2017, and December 31, 2024, at 15 hospitals in various regions of Fujian Province, a coastal southeastern city in China. Regions included Eastern Fujian, Southern Fujian, Western Fujian, Northern Fujian, and Central Fujian. The annual incidence of fetal laterality disorders was observed, and the association between the COVID-19 pandemic and the incidence of these disorders was assessed. Results: The total number of deliveries across the 15 hospitals was 721,562. Between 2017 and 2024, 566 cases of fetal visceral laterality disorders were diagnosed by prenatal ultrasound, including 178 cases of complete situs inversus, 139 cases of partial situs inversus, and 249 cases of heterotaxy syndrome (HS). During the COVID-19 infection period, the incidence of fetal laterality disorders showed an increasing trend from 2020 to 2024 ( Conclusion: This study suggests an increased incidence of fetal visceral laterality disorders during the COVID-19 pandemic. It provides insights for further related research.