Taabo Multigenerational Birth Cohort in Côte d'Ivoire: Protocol for Establishing a Longitudinal Multigenerational Birth Cohort to Guide Health Policy.

Background: A large number of sociodemographic, economic, environmental, and psychosocial changes have contributed to the epidemiological transition of African countries and fundamentally shifted the primary drivers of health. Cohort studies are essential for understanding and improving population health but remain scarce in sub-Saharan Africa. Objective: The main objective of the Taabo Multigenerational Cohort (MGC) project is to establish a large, regionally representative multigenerational cohort. The cohort will be established within the Taabo Health and Demographic Surveillance System (HDSS) and used for studying the life course and intergenerational dynamics of disease in the south-central part of Côte d'Ivoire. Methods: The Taabo MGC project focuses on children born between January 1, 2024, and December 31, 2025, in the Taabo HDSS, as well as their parents, grandparents, and great-grandparents. Eligible women and their children are enrolled during pregnancy, and women who do not report during pregnancy are enrolled after the birth. After enrollment of pregnant women, biological ancestors of the index child who are still alive and living in the study area are recruited into the cohort. The cohort is expected to enroll at least 3000 pregnant women and their children, as well as the infants' fathers, grandparents, and great-grandparents, with an expected sample size of approximately 15,000 individuals. To ensure the entire local population is covered in this study, we will also include 100 adults without children. The baseline assessments cover data on demographics, household wealth, tobacco and alcohol consumption, diet, physical activity, health history, quality of life, environmental exposures, depression, anxiety, stress, resilience, obstetric history, birth outcomes, cognitive function, and, for older adults, physical performance. We will also collect anthropometric measurements, blood pressure, and hemoglobin levels and check for Plasmodium infection (the causative agent of malaria) among all participants. Results: As of December 2024, the Taabo MGC project has enrolled 3239 women and 6501 family members. The enrollment of pregnant women and their children's biological ancestors will continue until the end of 2025, aiming to reach at least 15,000 adults. Conclusions: The Taabo MGC project is designed to become one of the largest cohort studies in the region. Once established, the Taabo MGC project should become a platform for future observational and interventional studies at the local level and contribute to the much-needed evidence base on lifetime disease risk in this part of Côte d'Ivoire. We hope that our work will stimulate research and guide health policy elsewhere in sub-Saharan Africa.