Early Life Determinants of Child Health: A New Denver-Based Cohort - PROJECT SUMMARY Our overarching goal is to recruit and follow a new cohort of pregnant people and their partners, to implement longitudinal data collection using the ECHO Cohort Protocol, and to lead ECHO-wide analyses that advance understanding of when and how exposures during preconception, prenatal, and postnatal/lactational periods influence a broad range of child health outcomes. We will lead solution-oriented science to target adverse environmental exposures that may be prevented through policy, programs, and practices, and to identify positive influences in the preconception, prenatal, and postnatal periods that may be promoted to mitigate health risks associated with adverse early-life exposures. We will leverage our local investigator and staff expertise to enroll pregnant people, their conceiving partners, and their offspring from a large network of Federally Qualified Health Centers serving a racially, ethnically, and socioeconomically diverse population in Denver, Colorado. In Aim 1, we propose to utilize the breadth of Core data elements in the ECHO Cohort Protocol to answer solution-oriented research questions regarding the link between early-life exposures and childhood health outcomes, and to identify modifiable prenatal and postnatal factors that may minimize risk. In Aim 2, we propose to implement novel and scalable Specialized measures to determine biological pathways linking parent and family lifestyle factors and the physical/chemical environment of early life with child obesity and neurodevelopment, and to identify susceptible periods for these exposures in early life. In Aim 3, we describe our plans to recruit and follow a diverse cohort of over 800 pregnant people with their conceiving partner and offspring, and to additionally enroll over 300 participants with a high probability of subsequent pregnancy into a preconception study. In Aim 4, we propose research questions that utilize data elements collected during the preconception period, to identify parental preconception exposures that adversely affect child health outcomes, and to describe molecular markers that may mediate these effects. Our team of expert investigators is well-positioned to contribute to the development of the ECHO specialized exposure and outcome protocols, and to the design and implementation the preconception pilot study. Our experienced staff and MPI team will ensure successful recruitment and implementation of the ECHO Cohort Protocol to provide a robust sample size and high-quality data. We will lead ECHO-wide analyses to address pressing questions in the early-life origins of child health and disease, and to identify potential targets for prevention of adverse environmental exposures and for promotion of protective factors in early life.