The growing recognition of maternal health's impact on offspring necessitates large-scale prospective cohort studies spanning the maternal-child life cycle. This study establishes a family-centered birth cohort of 100,000 Chinese participants, tracking from preconception through offspring adolescence to investigate early-life health trajectories and intergenerational transmission of diseases, health status, and psychological-behavioral patterns. Data collection includes biospecimens (placenta, cord blood, breast milk, blood, urine, feces) and multi-omics analysis (genomic, proteomic, metabolomic, microbiomic), alongside clinical information from preconception, pregnancy, birth through childhood (0-14 years). The cohort covers 24 stratified sites across China, incorporating real-time environmental monitoring (air pollution, meteorological data) and sociogeographic factors. Targeting reproductive-age couples (18-45 years) and their offspring, the study addresses multigenerational health linkages, urban-rural disparities, and regional diversity from 2025 to 2039. By integrating genetic, environmental and lifestyle data, this research will identify critical intervention windows and mechanisms for chronic disease transmission across generations, supporting China's "Healthy China" initiative and developing targeted strategies for population health and aging.