Digital Health–Based Peer Support Ecosystem for Gestational Diabetes Mellitus in Vietnam (VALID II Study): Multistakeholder Cocreation and Pilot Study

Background: Gestational diabetes mellitus (GDM) is associated with fetal overgrowth, increased risks of perinatal morbidity and mortality, and long-term complications for mother and child, including cardiovascular disease and type 2 diabetes. Innovative, peer-based digital health interventions are emerging globally as a potential approach to assist and empower women in effective self-care and well-being during pregnancy. However, there remains substantial potential to develop and evaluate culturally sensitive digital health interventions for pregnant women with GDM, especially in low- and middle-income countries. Objective: This study aimed to bridge the gap between the World Health Organization (WHO) self-care framework and local practice by designing and piloting the "Healthy Pregnancy" intervention, a multiplatform digital ecosystem for women with GDM in northern Vietnam, through a staged cocreation and pilot refinement process. Methods: Between December 2022 and February 2024, drawing on the WHO's conceptual framework for self-care and cocreation approach, we iteratively developed "Healthy Pregnancy," a digital health intervention, in 4 stages: (1) formative studies and self-care construct prioritization, (2) cocreation processes with key stakeholders, (3) development and design translation, and (4) pilot testing and final refinement. Results: In stage 1, we identified gaps in current digital health interventions in low- and middle-income countries, explored the sociocultural realities of women with GDM in Vietnam, and prioritized 7 self-care constructs. In stage 2, we conducted a cocreation workshop to enable key stakeholders to co-design the foundational infrastructure for the potential intervention. In stage 3, we established a multicomponent digital intervention ecosystem with explicitly defined operating workflows. Finally, in stage 4, we gathered suggestions for a digital health intervention from a pilot test group of pregnant women with GDM, to refine and optimize the system schematic and information flow before moving to the real intervention. Conclusions: By applying a cocreation approach across all stages of development of the "Healthy Pregnancy" digital health intervention, from problem identification to solution development and evaluation, we developed a locally tailored GDM self-care model. This process not only addressed gaps in standard care but also empowered pregnant women through a supportive, multiple-stakeholder environment. This study demonstrates a rigorous cocreation pathway for systematically translating WHO self-care constructs into a feasible, culturally adapted digital ecosystem for GDM in Vietnam and offers a transferable, people-centered design process alongside a practical blueprint for integration into routine maternal care.