Congenital heart disease (CHD) is the most common congenital anomaly, but whether the COVID-19 pandemic affects its prevalence is unknown. We aimed to compare the incidence of CHD during the COVID-19 pandemic with that before the pandemic in China.

This multicenter retrospective observational study involved all newborns in seven representative cities of China between 01 September 2019, and 31 December 2021. All the newborns underwent pulse oximetry monitoring combined with cardiac murmur auscultation in the first 6 h to 72 h after birth for CHD screening. We defined fetuses born in and beyond September 2020 as the exposed group, and before as the non-exposed group. The incidence of CHD and specific heart abnormalities, including atrial septal defect (ASD) and ventricular septal defect (VSD), before and during the COVID-19 pandemic were compared.

The study included 492,662 newborns; 217,003 newborns born before September 2020 and 275,659 newborns born in and beyond September 2020. There were 3115 patients with CHD in total during the whole study period. Of those, 1055 (September 2019 to August 2020) and 2060 (September 2020 to December 2021) were less and more affected by the pandemic, respectively. There was a significant increase in the incidence of CHD in the early stage of the COVID-19 pandemic (7.78 per 1000 births) compared to that before the pandemic (4.86 per 1000 births) (p < 0.001). The birth prevalence of ASD and VSD significantly increased during the pandemic from 3.991 per 1000 births to 4.717 per 1000 births (p = 0.008) and from 1.650 per 1000 births to 3.508 per 1000 births (p < 0.001), respectively.

The incidence of CHD increased during the COVID-19 pandemic, which was possibly related to the reallocation of medical resources, increased psychological pressure, and increased socioeconomic deprivation, though underlying mechanisms remain unclear.