Association of Primary Language with Provision of Mother's Milk Among Very-Low-Birthweight Infants in Massachusetts

Background: Racial/ethnic inequities in mother's milk provision for hospitalized preterm infants persist. The extent to which primary language contributes to these racial/ethnic inequities is unknown.Objective: Examine associations of maternal race/ethnicity and primary language with (1) any/exclusive mother's milk at hospital discharge and (2) the time to cessation of mother's milk provision during the hospitalization.Methods: We examined 652 mother/very-low-birthweight (VLBW) infant dyads at 9 level 3 neonatal intensive care units in Massachusetts from January 2017 to December 2018. We abstracted maternal race/ethnicity and language from medical records, and examined English and non-English-speaking non-Hispanic White (NHW), non-Hispanic Black (NHB), and Hispanic mothers of any race. We examined associations of race/ethnicity and language with (1) any/exclusive mother's milk at discharge (yes/no) using mixed-effects logistic regression and (2) cessation of mother's milk during the hospitalization using cox proportional hazard models, adjusting for gestational age, birthweight, and accounting for clustering by plurality and hospital.Results: Fifty-three percent were English-speaking NHW, 22% English-speaking NHB, 4% non-English-speaking NHB, 14% English-speaking Hispanic, and 7% non-English-speaking Hispanic. Compared with English-speaking NHW, NHB mothers (English adjusted odds ratio [aOR] 0.28 [0.17, 0.44]; and non-English-speaking aOR 0.55 [0.19, 0.98]), and non-English-speaking Hispanic mothers (aOR 0.29 [0.21, 0.87]) had lower odds of any mother's milk at discharge. In time-to-event analyses, non-English-speaking Hispanic (adjusted hazard ratio [aHR] 4.37 [2.20, 6.02]) and English-speaking NHB mothers (aHR 3.91 [1.41, 7.61] had the earliest cessation of mother's milk provision.Conclusion: In Massachusetts, maternal primary language was associated with inequities in mother's milk provision for VLBW infants with a differential effect for NHB and Hispanic mothers.