About the DiGest Study:
Gestational diabetes affects 35,000 pregnancies annually in the UK, causing health problems for mother and child, such as large-for-gestational age (LGA) and difficult deliveries. Obesity and excessive weight gain in pregnancy are risk factors for gestational diabetes. However, it is unclear if weight gain remains important in women after diagnosis (28 weeks). National guidelines give no calorie or weight targets to guide management.
Data from our hospital clinic suggests that women who avoid excessive weight gain during pregnancy, particularly after a diagnosis of gestational diabetes, had improved pregnancy outcomes, needed less medical intervention during labour and gave birth to infants with a healthier birthweight and had lower rates of large-for-gestational- age (LGA). Women with a reduced weight gain after diagnosis also had better postnatal glucose tolerance. This raises the exciting possibility that an 8-10 week intervention in late pregnancy could improve pregnancy outcomes and also reduce maternal diabetes risk long-term.
This study is a multicentre, prospective, randomised, controlled, double-blind trial to assess the effects of a reduced calorie diet in late pregnancy in women with gestational diabetes. Overweight or obese women with gestational diabetes will be randomised to receive standard-calorie or reduced-calorie diet boxes containing all meals from 30 weeks to delivery. Food diaries, continuous glucose monitoring, Bluetooth scales and questionnaires will measure compliance, glucose control, weight changes and quality of life. Women will receive standard antenatal GDM care including regular ultrasound scans and treatment (insulin and/or metformin) as needed. The study will assess if an 8-10 week intervention can reduce maternal weight gain (primary maternal endpoint) and infant standardised birthweight (primary neonatal endpoint). Secondary endpoints include delivery modality, maternal treatment requirements, maternal and neonatal complications and maternal antenatal and postnatal glucose concentrations. The DiGest study is expected to take 5 years with results anticipated in 2023-2024.