Exclusive Breastfeeding in the Northwest: Disparities Related to Race/Ethnicity and Substance Use

Mothers who are Black, Indigenous, and people of color (BIPOC) are disproportionately impacted by substance use in pregnancy and less likely to breastfeed. Our objectives were to assess relationships between substance use in pregnancy and exclusive breastfeeding at discharge (EBF) and race/ethnicity and EBF, and determine the extent to which substance use influences the relationship between race/ethnicity and EBF.

This is a retrospective cohort study of term mother-infant dyads using 2016 to 2019 data from a Northwest quality improvement collaborative, Obstetrical Care Outcomes Assessment Program. Stepwise and stratified multivariable logistic regression analyses were conducted to determine associations between independent variables consisting of characteristics, including maternal race/ethnicity and substance use, and the dependent variable, EBF.

Our sample consisted of 84,742 dyads, 69.5% of whom had EBF. The adjusted odds of EBF for non-Hispanic Black and Hispanic mothers were half, and for American Indian/Alaska Native mothers two-thirds, that of White mothers (aOR [95% CI]: 0.52 [0.48, 0.57], 0.51 [0.48, 0.54], 0.64 [0.55, 0.76], respectively). Substance use did not mediate the association between race/ethnicity and EBF, but it modified the association. Among those reporting nicotine or marijuana use, Hispanic mothers were half as likely as White mothers were to exclusively breastfeed. Other factors associated with a lower likelihood of EBF included public or no insurance, rural setting, C-section, NICU admission, and LBW.

Disparities in EBF related to race/ethnicity and substance use were pronounced in this study, particularly among Hispanic mothers with nicotine or marijuana use.