BELLEVUE, WASH. – Louisiana has marked black-white racial disparities when it comes to birth defects, suggests a cohort study of 113,696 live births in the state during 2006-2008.
Relative to peers born to black mothers, infants born to white mothers were 24%-177% more likely to have cardiac, gastrointestinal, and genitourinary defects, according to data reported at the annual meeting of the Teratology Society. But they were 35% less likely to have microcephalus.
"We can conclude from this study that most birth defects are more common in non-Hispanic white children, compared to non-Hispanic black children. We think this difference may be the result of genetic susceptibility or environmental factors that play a significant role," said Dr. Tri Tran, of the department of pediatrics at the Louisiana State University Health Sciences Center and an investigator with the Louisiana Department of Health and Hospitals Office of Public Health children and youth with special health needs program – both in New Orleans.
In the future, the investigators hope to conduct more in-depth study of genetic and environmental factors to determine reasons for the observed disparities, which could help inform effective prevention and intervention strategies, he added.
Session cochair Dr. James Mills, an investigator with the Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Md., commented, "I noticed that some of the defects that were more common in whites are things like ASD [atrial septal defect], VSD [ventricular septal defect], PDA [patent ductus arteriosus], and hypospadias, where there may be fairly trivial defects but really good diagnosis. Did you look at the data by socioeconomic class to see if there may be some bias in ascertainment?"
Analyses did not include that potential confounder, Dr. Tran replied.
For the study, the investigators used linked hospital records and data from the Louisiana Birth Defects Monitoring Network, a population-based surveillance system, to identify live births to non-Hispanic white women (57%) and non-Hispanic black women (43%) in which the birth weight was at least 350 g, and the gestational age was at least 20 weeks.
The investigators assessed birth defects captured in the first 3 years of life. Results were restricted to the 19 birth defects seen in at least 30 infants.
In adjusted analyses, infants born to white women were more likely to have ventricular septal defects (prevalence ratio, 1.59), atrial septal defects (1.24), atrioventricular septal defects (1.67), patent ductus arteriosus (1.31), cleft palate without cleft lip (2.20), pyloric stenosis (2.77), obstructive genitourinary defects (1.31), gastroschisis (2.71), Down syndrome (1.49), and hypospadias (1.50).
Only a single birth defect, microcephalus, was significantly less common in infants of white women, compared with infants of black women (prevalence ratio, 0.65), reported Dr. Tran.
Dr. Tran disclosed no relevant conflicts of interest.