Of the 16,194 birth defects among 561,745 live births in metropolitan Atlanta from 1994 through 2005, NHW people had the highest prevalence of any birth defects (323 per 10,000 live births) followed by NHB people (266 per 10,000 live births) and Hispanic people (266 per 10,000 live births) (). After adjustment for maternal age, child sex, gravidity, and SES, births to both NHB and Hispanic women had a lower overall prevalence than births to NHW women (NHB women: adjusted PR=0.85, 95% CI 0.81, 0.88; Hispanic women: adjusted PR=0.86, 95% CI 0.81, 0.90). Of the 44 defect groups analyzed, the adjusted PR was <1 for 25 defects (57%) among both NHB and Hispanic infants. The overall prevalence for birth defects among Hispanic and NHB infants was similar (adjusted PR=1.02, 95% CI 0.96, 1.07), and 43% (n=18) of individual defect groups had a higher prevalence among Hispanic infants than among NHB infants.
Adjusteda prevalence ratios and 95% confidence intervals for selected congenital defects among non-Hispanic white, non-Hispanic black, and Hispanic infants: metropolitan Atlanta, 1994–2005
Five defects had a statistically significantly higher prevalence among NHB vs. NHW infants: Hirschsprung disease, polydactyly, trisomy 13 or 18, cystic kidney, and secundum atrial septal defect (ASD). Compared with NHW infants, NHB infants had a lower prevalence of 10 defects: congenital dislocation or dysplasia of the hip, pyloric stenosis, aortic stenosis, craniosynostosis, muscular ventricular septal defect (VSD), spina bifida, cleft lip with or without cleft palate, cleft palate, clubfoot without spina bifida, and hypospadias.
Four defects had a statistically significantly higher prevalence among Hispanic vs. NHW infants: ASD, muscular VSD, diaphragmatic hernia, and any trisomy syndrome. Compared with NHW infants, Hispanic infants had a lower prevalence of hypospadias, pyloric stenosis, coarctation of the aorta, avioventricular septal defect (AVSD), clubfoot, and congenital dislocation or dysplasia of the hip.
The comparison of Hispanic children with NHB children had the greatest number of defects (n=20) for which disparities existed. Of the 12 defects that had a statistically significant higher prevalence among Hispanic infants, six had an adjusted PR equal to or exceeding twice that for NHB infants.
There was evidence of an interaction between race/ethnicity and CT poverty level for any defect and for a number of individual defects (43%); however, very small population sizes in many of the stratified analyses prohibited interpretable findings. For the few defects with sufficient data, there were no consistent patterns for the role of SES on racial/ethnic disparities in the prevalence of birth defects (). The limited population size similarly limited the interpretability of the subanalysis examining maternal nativity. There was limited evidence of variations in prevalence by maternal nativity (). The strongest evidence was with gastroschisis, for which there was a lower prevalence among foreign-born Hispanic vs. U.S.-born Hispanic children (PR=0.32, 95% CI 0.14, 0.76). Foreign-born NHW children were more likely than their U.S.-born counterparts to have congenital dislocation of the hip (PR=1.68, 95% CI 1.09, 2.59). The prevalence of Down syndrome was twice as high among foreign-born compared with U.S.-born mothers for NHB (PR=1.93, 95% CI 1.34, 2.79) and Hispanic (PR=2.17, 95% CI 0.80, 5.92) people. Foreign-born NHB children were also more likely than their U.S.-born counterparts to have an increased prevalence of hypospadias (PR=1.35, 95% CI 1.07, 1.71) and several congenital heart defects including complete AVSD (PR=2.33, 95% CI 1.10, 4.94), transposition of the great arteries (PR=2.79, 95% CI 1.34, 5.78), aortic stenosis (PR=7.25, 95% CI 1.81, 28.99), and muscular VSD (PR=1.81, 95% CI 1.33, 2.47).
Adjusted prevalence ratiosa and 95% confidence intervals for selected birth defects by race/ethnicity and level of SES:b metropolitan Atlanta, 1994–2005
Prevalence ratiosa of non-native vs. U.S. native-bornb mothers by race/ethnicity for select birth defects,c 1997–2005