Rationale and design of a comparative effectiveness trial to prevent type 2 diabetes in mothers and children: the ENCOURAGE healthy families study.

The number of youth with type 2 diabetes (T2D) is expected to quadruple over 4 decades. Gestational diabetes mellitus (GDM) is also increasing and is linked with development of T2D in women, and greater risk for T2D in adolescents exposed to GDM. Despite the increasing prevalence of T2D, approaches to prevent diabetes in high-risk youth and families are rare.