Overall aim:~To study the feasibility and acceptability and safety of an intermittent low-energy diet (ILED) amongst women with gestational diabetes (GDM). Also the feasibility of a randomised controlled trial (RCT) of ILED compared to best NHS care in these women.~Background:~Up to 16% of pregnant women in the UK develop GDM with rising rates due to increasing rates of obesity and maternal age. GDM affects both maternal and neonatal outcomes and is a high burden to patients and the NHS through frequent clinic visits, monitoring, and costly medications such as insulin. The National Institute for Health and Care Excellence (NICE) guidelines advocate healthy diet (with increased physical activity [PA]) as first-line therapy for GDM with approximately 30% progressing to metformin and/or insulin treatment. Women with GDM are keen for alternative dietary interventions to reduce their need for medications. It has been shown that intermittent low energy diets improve glycaemic control in type-2 diabetes. The investigators wish to test the utility of ILED in GDM.~Aims: To explore the feasibility of using an ILED in the management of GDM with the objective of conducting a large, statistically powered RCT of ILED vs. best NHS care.~Primary Objectives of the feasibility study: 1. Uptake, recruitment rate and retention to a RCT of ILED vs. best NHS care 2. Adherence to dietary allocation within the ILED and best NHS care groups. 3. Safety outcomes with ILED including episodes of maternal hypoglycaemia or ketonaemia 4. The suitability of progression to medication as a suitable endpoint for a future definitive study.~Method:~48 women diagnosed with GDM and obesity (BMI ≥30kg/m2, or ≥27.5kg/m2 in high risk ethnic minority groups) will be randomized 1:1 to an ILED and physical activity intervention or best NHS Care (healthy diet and physical activity) for the third trimester of pregnancy. Both groups will receive the relevant diet and physical activity advice and fortnightly phone support by the study dietician until delivery. Participants will also undergo standard maternal and foetal assessments at baseline, delivery and 12 weeks post-delivery including weight and maternal metabolic parameters. Adherence to the diet and physical activity will be assessed using food records and a diet quality and physical activity questionnaires. The percentage of women in each group requiring metformin and/or insulin, and differences in capillary glucose profiles, HbA1c, insulin, c-peptide and HOMA-IR between the two groups will be analysed.~Qualitative evaluation:~Investigators will undertake qualitative analysis of the experiences and thoughts of 5 participants per group and healthcare professionals delivering the interventions.~Anticipated impact and dissemination:~This study will inform the feasibility and design of a definitive RCT of ILED versus best NHS care in GDM. Findings will be disseminated to health professionals and patients through published articles, conference presentations and patient networks in collaboration with the patient and public involvement and engagement panel.
Non blinded randomised feasibility trial designed to assess the feasibility, safety, and acceptability of an intermittent low energy diet (ILED) vs best National Health Service (NHS) care in gestational diabetes.