Co-occurrence of congenital anomalies by maternal race/ethnicity among infants and fetuses with Down syndrome, 2013-2017: A U.S. population-based analysis

Background: Individuals with Down syndrome (DS) have a higher prevalence of additional congenital anomalies, especially cardiovascular defects, compared to the general population. Several reports have indicated that the prevalence of DS among live births varies by race and ethnicity within the United States. We aim to examine variations in co-occurring congenital anomalies by maternal race/ethnicity among infants and fetuses diagnosed with DS born during 2013-2017.

Methods: State birth defect surveillance systems (N = 12) submitted data on infants and fetuses diagnosed with DS born during 2013-2017. We calculated the prevalence of co-occurring major and minor congenital anomalies, by organ system, and four selected cardiovascular birth defects, all stratified by maternal race/ethnicity.

Results: Among 5,836 cases of DS, 79.7% had one or more co-occurring congenital anomalies. There was a higher percentage of co-occurring congenital anomalies among infants and fetuses born to Hispanic mothers. The lowest percentage of co-occurring congenital anomalies, including three out of the four individual cardiovascular conditions examined, was among infants/fetuses born to non-Hispanic American Indian/Alaska Native mothers.

Conclusions: We describe differences in DS co-occurrence with additional congenital anomalies among maternal racial/ethnic groups. These data may help focus future research on differences among racial/ethnic groups in the diagnosis and reporting of co-occurring congenital anomalies in infants/fetuses diagnosed with DS.