The following is a summary of “Adverse Maternal Fetal Environment Partially Mediates Disparate Outcomes in Non-White Neonates with Major Congenital Heart Disease,” published in the December 2022 issue of Pediatrics by Santana, et al.

For a study, researchers sought to ascertain if diverse prenatal exposure to a harmful mother environment contributed to the variable outcomes in newborns with severe congenital heart disease (CHD).

The population-based administrative database was used in retrospective cohort research in California (2011-2017). The main exposure was to race and ethnicity. Primary mediator: Unfavorable maternal-fetal environment, as shown by signs of maternal metabolic syndrome and/or maternal placental syndrome. A composite of days alive outside of hospitals throughout the first year of life and 1-year death or serious morbidity (DAOOH) were the results. After correcting for CHD severity, mediation studies evaluated the percent contributions of mediators on pathways between race/ethnicity and outcomes.

About 5,244 Hispanic, 625 non-Hispanic Black and 2,747 non-Hispanic White newborns (the reference group) were all included. Hispanic or non-Hispanic Black Infants were more likely to experience a composite outcome (crude OR: 1.18; crude OR: 1.25, respectively) and had less DAOOH (-6 & -12 days, respectively). Newborns of non-Hispanic Black women had greater rates of maternal metabolic syndrome (43% vs. 28%; OR: 1.97) and maternal placental syndrome (18% vs. 12%; OR, 1.66) exposure compared to infants of Hispanic mothers (43% vs. 28%; OR: 1.89). Exposure to maternal placental syndrome (OR: 1.56) and maternal metabolic syndrome (OR: 1.21) were both linked to a composite result and less DAOOH (-25 & -16 days, respectively). The difference between the non-Hispanic Black race, and the composite result was explained by the adverse maternal-fetal environment in 25% of cases and by Hispanic ethnicity in 18% of cases. Negative maternal fetal environments accounted for 16% of the link with DAOOH in non-Hispanic Black races and 21% in Hispanic ethnic groups.

Racial and ethnic inequalities in major CHD outcomes are mostly attributed to increased exposure to unfavorable maternal prenatal environments.