A co-created self-care and informal support intervention targeting women with gestational diabetes mellitus in northern Vietnam (VALID-II): a protocol for a two-arm non-randomised feasibility study.

Background: Gestational diabetes mellitus (GDM) is a transitory form of diabetes that presents during pregnancy with frequent adverse maternal and neonatal health consequences if left untreated. The prevalence of GDM is rapidly increasing in low- and middle-income countries such as Vietnam, and early sustainable interventions are important. The overall aim of this study-henceforth referred to as VALID-II-is to assess the feasibility of a co-created self-care and informal support intervention targeted at pregnant women with GDM. Further, the aim is to assess the potential efficacy of the intervention in reducing maternal and neonatal health complications compared with standard care.

Methods: VALID-II is a two-site, two-arm, non-randomised feasibility intervention study in Thai Binh Province in northern Vietnam with a delayed start for the intervention group. The intervention study is nested in a larger cohort. In total, 2000 pregnant women will be screened for GDM, with an estimated 400 women screening positive according to the World Health Organisation-International Association of Diabetes and Pregnancy Study Group diagnostic criteria. First, 200 women who screen positive for GDM will be assigned to a control group that will receive standard care. Among the 200 women, 20 will take part in an in-depth ethnographic study along with their family members, and the intervention will be co-created with them. Second, once the intervention has been created, 200 women will be assigned to the intervention group, which will receive the intervention plus standard care. Twenty women and their families from the intervention group will also take part in an ethnographic study. The primary outcome is to evaluate how feasible the self-care intervention is (composite outcome: recruitment, retention, and acceptability). Other secondary outcomes include the number of new-borns born large for gestational age, prevalence and risk factors for GDM, self-care agency, self-care, and breastfeeding practices.

Discussion: This study provides knowledge of the feasibility of informal/self-care and social support interventions and their preliminary impact on maternal and child health outcomes among women with GDM in northern Vietnam. Furthermore, it will inform parameters such as effect size and variance, which are essential for calculating the sample size needed to achieve the desired power in a future full-scale trial. This may guide decision makers in how to optimise the management of GDM in low- and middle-income contexts.

Trial registration: NCT05744856.

Trial status: Recruiting.