Objective: To explore variations in maternal and infant outcomes among clusters of mother–infant dyads in the NICU characterized by intersecting social identity characteristics. Design: Secondary exploratory analysis of data from a cluster randomized controlled trial conducted from December 2015 to July 2018. Setting: Ten Level II NICUs in six cities across Alberta, Canada. Participants: A total of 400 mothers and their preterm infants at 320⁄7 to 346⁄7 weeks gestation. Methods: We used two-step cluster analysis to identify clusters based on maternal ethnicity, education, age, and annual family income. We employed multiple regression models to examine whether cluster membership was associated with infant length of stay, maternal psychosocial distress, and parenting self-efficacy at discharge, controlling for relevant infant and maternal characteristics and hospital setting (urban vs. regional). Results: We identified four mother–infant dyad clusters: (1) younger, lower-education, lower-income White mothers; (2) older, higher-education, higher-income BIPOC (Black, Indigenous, or people of color) mothers; (3) diploma-educated, highest-income White mothers; and (4) university-educated, highest-income White mothers. Although cluster membership was not associated with maternal outcomes, infants of mothers in Cluster 1 had shorter lengths of stay compared with those in Cluster 4. Hospital setting was a predictor of length of stay and parenting self-efficacy. Conclusion: Findings highlight the relevance of social identity and hospital setting in shaping NICU outcomes and support the need for equity-informed neonatal care.





