Racial and socioeconomic disparities in breast milk feedings in US neonatal intensive care units

Abstract

Very low birth weight (VLBW; <1500 g birth weight) infants are substantially more likely to be born to black than to non-black mothers, predisposing them to potentially preventable morbidities that increase the risk for costly lifelong health problems. Mothers' own milk (MOM) may be considered the ultimate "personalized medicine" since milk composition and bioactive components vary among mothers and multiple milk constituents provide specific protection based on shared exposures between mother and infant. MOM feedings reduce the risks and associated costs of prematurity-associated morbidities, with the greatest reduction afforded by MOM through to NICU discharge. Although black and non-black mothers have similar lactation goals and initiation rates, black VLBW infants are half as likely to receive MOM at NICU discharge in the United States. Black mothers are significantly more likely to be low-income, single heads of household and have more children in the home, increasing the burden of MOM provision. Although rarely considered, the out-of-pocket and opportunity costs associated with providing MOM for VLBW infants are especially onerous for black mothers. When MOM is not available, the NICU assumes the costs of inferior substitutes for MOM, contributing further to disparate outcomes. Novel strategies to mitigate these disparities are urgently needed. IMPACT: Mother's own milk exemplifies personalized medicine through its unique biologic activity. Hospital factors and social determinants of health are associated with mother's own milk feedings for very low-birth-weight infants in the neonatal intensive care unit. Notably, out-of-pocket and opportunity costs associated with providing mother's own milk are borne by mothers. Conceptualizing mother's own milk feedings as an integral part of NICU care requires consideration of who bears the costs of MOM provision-the mother or the NICU?

Fig. 1. Determinants of an enabling breastfeeding environment.

Adapted with permission of Elsevier, from ref.  Permission conveyed through Copyright Clearance Center, Inc.

Fig. 2

Mother’s own milk bioactive components.

Fig. 3. US regional variation in any human milk at discharge by maternal race/ethnicity.

Reproduced with permission from ref.  Copyright© 2019 American Medical Association. All rights reserved. Permission conveyed through Copyright Clearance Center, Inc.

Fig. 4. Kolmogorov−Smirnov test of difference between racial-ethnic distribution of VPTB infants with increasing hospital neonatal morbidity-mortality rank.

Adapted with permission from ref.  Copyright© 2018 American Medical Association. All rights reserved. Permission conveyed through Copyright Clearance Center, Inc. Black and Hispanic VPTB infants are more likely to be born in New York City hospitals with higher risk-adjusted neonatal morbidity and mortality rates than are white VPTB infants. The dashed lines indicate the hospital rank cut-off at which 50% of infants are born for each race/ethnicity. The green line indicates that 50% white VPTB infants are born at hospitals that rank 1–20 in safety or have lower neonatal morbidity or mortality rates. The red line indicates that 50% Hispanic VPTB infants are born at hospitals that rank 1–21 in safety. The blue line indicates that 50% black VPTB infants are born at hospitals that rank 1–25 in safety. VPTB, very preterm birth.

Fig. 5. US breastfeeding rates from 1970 to 2015 by maternal race/ethnicity.

Based on data from refs. ^–