IntroductionIn the USA, Black birthing people and infants experience disproportionately worse pregnancy-related health outcomes. The causes for these disparities are unknown, but evidence suggests that they are likely socially and environmentally based. Efforts to identify the determinants of these racial disparities are urgently needed to elucidate the highest priority targets for intervention. The Birth and Beyond (BABY) study evaluates how micro-level (eg, interpersonal and family) and macro-level (eg, neighbourhood and environmental) risk and resiliency factors transact to shape birth person-infant health, and underlying psychobiological mechanisms.Methods and analysisThe BABY study will follow 350 Black families (birthing parents, non-birthing parents and infants) from pregnancy through the first postpartum year, with research visits during pregnancy and at infant ages 6 and 12 months. Research visits comprise a combination of interview about a range of recent and life course stress and resiliency exposures and supports, psychophysiological (sympathetic, parasympathetic and adrenocortical) assessment and behavioural observations of parent–infant coregulatory behaviours. Spatial analyses are completed by mapping parent current and past residential addresses onto archival public data (eg, about neighbourhood quality and racial segregation). Finally, EMRs are abstracted for information about birthing parent relevant medical history, pregnancy conditions and infant birth outcomes. Analyses will evaluate the risk and resiliency mechanisms that contribute to pregnancy and birth-related outcomes for Black birthing people and their infants, and the protective role of individual, familial, cultural, and community supports.Ethics and disseminationThe BABY study has been approved by the Institutional Review Board at Albany Medical Centre. The study team consulted with local organisations and groups comprised of stakeholders and community leaders and continues to do so throughout the study. Research results will be disseminated with the scientific and local community as appropriate.