382 - Trends and socio-demographic disparities in U.S. Congenital Anomalies (2016-2023)

Publication Number: 382.6845

Naveed Hussain, Connecticut Children's Medical Center, Farmington, CT, United States; Ramesh Vidavalur, Cayuga Medical Center/ Weill Cornell Medicine, Ithaca, NY, United States; Mahmoud Ali, West Virginia University Children's Hospital, Morgantown, WV, United States

Background: Congenital anomalies are mainly multifactorial, shaped by genetic and environmental factors. While folic acid supplementation has greatly reduced neural tube defects, data on modifiable socio-demographic risk factors and their impact on the prevalence of congenital anomalies is limited.

Objective: To investigate the trends and heterogeneity in the prevalence of congenital anomalies across the United States based on socio-demographic factors.

Design/Methods: This study analyzed data from the CDC-WONDER natality database between 2016 and 2023. The anomalies included were anencephaly, meningomyelocele/spina bifida, cyanotic congenital heart disease, congenital diaphragmatic hernia, omphalocele, gastroschisis, limb reduction defect, cleft lip with or without cleft palate, cleft palate alone, Down syndrome, suspected chromosomal disorders, and hypospadias. Association of maternal factors such as age, BMI, race, and other sociodemographic risk factors were examined. Pooled prevalence rates were calculated per 1,000 live births. Bivariate analyses assessed the impacts of race, maternal BMI, tobacco use, maternal age, and assisted reproductive technologies. Descriptive statistics were used to derive relative risk (RR) with 95% confidence intervals, using MedCalc Statistical Software version 19.2.6. Joinpoint regression analysis (version 5.2.0, National Cancer Institute, USA) was deployed to determine annual percent changes (APC) with statistical significance set at p<.05

Results: Among 3,482,944 births, the prevalence rate of congenital anomalies was 3.3 per 1,000 live births. Compared to White infants, Asian infants had a lower risk (RR 0.57 [95% CI: 0.52, 0.63]), as did Black infants (RR 0.81 [95% CI: 0.76, 0.85]) (Figure 1). In contrast, American Indian/Alaskan Native infants showed higher prevalence rates. Key socio-demographic risk factors identified included pre-pregnancy diabetes (RR 2.41 [95% CI: 2.16, 2.69], p<.001), advanced maternal age (>45 years) (RR 2.95 [95% CI: 2.36, 3.69], p<.001), and tobacco use (RR 1.78 [95% CI: 1.64, 1.94], p<.001) (Figure 2). A statistically significant downward trend was observed from 2016 to 2023 (APC: -0.6% [95% CI: -1.1, -0.2], p<.006) (Figure 3).

Conclusion(s): This study shows a declining trend in congenital anomalies prevalence in the U.S. Ongoing national monitoring is crucial for tracking these trends, guiding prevention strategies, assessing legislative impacts on reproductive health, and understanding modifiable risk factors. Further research should investigate regional variations in specific birth defects and their socio-demographic associations.

Relative Risk Estimates by Race.
Blue dots represent relative risk and error bars represent 95% confidence interval.

Relative Risk Estimates by Other Socio-demographic Factors.
Error bars represent 95% confidence interval.

Joinpoint Regression Showing Prevalence Trend of Congenital Anomalies.
Inset represent annual percent change (APC)