Experience and Acceptability of a Reduced-Energy Whole-Diet Intervention in Women with Gestational Diabetes: a Qualitative Study of the Dietary Intervention in Gestational Diabetes Trial

Background: Gestational diabetes mellitus (GDM) is rising in prevalence in many countries worldwide. Although dietary modifications are the first-line treatment for GDM, it is unclear which specific dietary approaches are most effective to improve maternal and offspring outcomes while reducing further maternal weight gain. We recently demonstrated benefits of an energy-restricted diet with modest weight loss in women with GDM. Objectives: , in a free-living environment, and to examine potential barriers and enablers of implementation of such a diet into standard clinical care. Methods: This qualitative research study used semistructured interviews with 20 participants in the Dietary Intervention in Gestational Diabetes trial, in which women with GDM were randomized to a whole-diet intervention containing 1200 or 2000 kcal/d. We used reflexive thematic analysis to explore participants' experiences of the study diet and GDM. Results: We identified 6 key themes in participants' experience: emotional and cognitive burden of managing GDM, convenience of meal delivery, support and reassurance, hunger and appetite differences, health impacts for intervention engagement, and research participation for awareness and impact. Facilitators of study participation included support, motivation, convenience, and not wanting to be medicated. Barriers to participation were the social aspects of eating food, inconvenience, and uncertainty about the validity of dietary interventions. It was identified that participants frequently overlooked their physical health and weight management during pregnancy, despite how crucial these factors are for both maternal and infant well-being. Conclusions: Pregnant women with GDM found an energy-restricted diet to be acceptable and beneficial to emotional and physical health, especially when support is provided by healthcare professionals. The convenience of meal delivery and the motivations to avoid medication use in pregnancy facilitated engagement with the intervention.This trial was registered at ISRCTN registry as ISRCTN 65152174 (https://www.isrctn.com/ISRCTN65152174).