Large population-based assessment of SARS-CoV-2 teratogenicity by profiling congenital anomalies during COVID-19 pandemic.

Objective: This study examined population-level trends in congenital anomalies before and during the coronavirus disease-19 (COVID-19) pandemic in India, which experienced one of the most severe COVID-19 outbreaks with multiple devastating waves. Material and Methods: We conducted a retrospective analysis of prospectively collected data from the Antenatal Detection of Congenital Anomalies registry between pre-pandemic (January 2018-May 2020) and pandemic (June 2020-December 2022). Time series analysis examined temporal trends and seasonal patterns. Results: Among 175,749 prenatal scans, 2.895 congenital anomalies were detected (overall rate 16.5 per 1,000 scans). Detection rates were similar pre-pandemic (14.8 per 1,000 scans, n=1.370) and during the pandemic (18.3 per 1.000 scans, n=1.525; p=0.096). The distribution of anomalies by organ system remained consistent, with head/neck and genitourinary anomalies predominating (19-23% and 14-22% annually, respectively). A persistent seasonal pattern was observed, with peaks in the fourth quarter annually (mean November: 62.7 cases) and troughs at the beginning of each year (mean January: 36.8 cases). The Seasonal Autoregressive Integrated Moving Average model accurately predicted 2023 trends confirming the stability of the epidemiologic process. Conclusion: Our large-scale study provides compelling evidence that the COVID-19 pandemic was not associated with a change in the rate or pattern of congenital anomalies at the population level. The discovery of a robust seasonal variation in anomaly detection represents a significant finding that demands detailed delineation to inform preventive strategies.