PROJECT SUMMARY Ensuring equitable breastfeeding support is essential, as breastfeeding rates among Hispanic and non- Hispanic Black (Black) individuals decline significantly beyond birth. Specifically, approximately 80% of Hispanic and Black infants are breastfeed at birth, but only half continue receiving breastmilk at 6 months and one-third at 12 months of age, respectively. Social determinants of health and equity (i.e., environmental factors, healthcare practices, state legislation) play pivotal roles in shaping breastfeeding outcomes among minoritized individuals. While successful strategies exist, including integrated lactation services and community resources, their accessibility is influenced by environmental characteristics, with affluent neighborhoods proving more conducive to sustained breastfeeding. Recognizing the need for improved access to breastfeeding resources, virtual lactation support (telelactation) emerges as a potential solution to address breastfeeding disparities that affect Hispanic and Black populations, but its effectiveness across demographic and socioeconomic lines in minoritized populations is nascent. To address this evidence gap, this project highlights the potential of telelactation in bridging the gap between lactation support needs and access for Hispanic and Black individuals in underserved neighborhoods. The proposed supplement is a secondary analysis of data from the Tele-MILC study, which is an innovative “siteless” randomized controlled trial to evaluate the impact of telelactation on breastfeeding outcomes. This project will include 1,459 Hispanic and Black participants surveyed at baseline, 1-month, and 6-months. The study arms included a treatment arm who accessed Pacify Health's app, offering 24/7 telelactation visits, while the control arm received standard care, monitored for potential contamination; both arms were followed through 24 weeks postpartum. Quantitative data on breastfeeding duration and exclusivity using self-reported measures at 4 and 24 weeks will be included, as well as indicators of social determinants of health and equity (e.g., Neighborhood Deprivation Index, availability of obstetric care providers) to quantify structural (dis)advantages of participants. The specific aims are: 1) Describe the extent to which there are differences in the social, environmental, and structural factors of parents in the Tele-MILC study by race/ethnicity; 2) Identify associations between breastfeeding outcomes and the social determinants of health and equity, and structural factors (examined in Aim 1) that impact maternal health; 3) Examine the extent to which living in an under-resourced environment or in a state with less supportive breastfeeding policies moderates the relationship between access to telelactation and breastfeeding duration and exclusivity among Hispanic and Black individuals. This study explores the effectiveness of telelactation as a potential solution to improve breastfeeding rate...