The Effect of Lifestyle Interventions on Glycemia in Diabetes Mellitus During Pregnancy: A Systematic Review

OBJECTIVES: Globally, 1 in 7 of all pregnancies are disrupted by diabetes, bestowing immediate and long-term health risks to mother and child. While diet and exercise are commonly prescribed in clinical practise to manage dysglycemia during pregnancy, the independent and combined effectiveness of diet and exercise across populations and types of diabetes (type-1, type-2, or gestational diabetes mellitus) is uncertain. To inform prevention strategies, the effects of distinct independent and combined diet and exercise strategies on gestational dysglycemia were synthesised and evaluated. METHODS: A systematic search for randomised controlled trials (published after 2000) that investigated the effect of diet and/or exercise interventions on glycemia in pregnant women diagnosed with diabetes was designed for AMED, EMBASE, MEDLINE (via OVID), PubMed, and Scopus. Random effects models were used to test the generalizability of results across studies and within key subgroups stratified by known confounders of gestational dysglycemia (e.g., age, ethnicity, BMI). This project is registered on PROSPERO (CRD42021268977). RESULTS: Following title-abstract screening of 4803 abstracts, 59 RCTs were included for full-text screening. and 16 studies with 1034 participants were suitable for quantitative analysis. Of these 16 studies, 9 were supplementation-based, 3 were dietary interventions, and 4 were exercise interventions. Furthermore, all studies identified via the systematic search strategy were conducted in patients diagnosed with gestational diabetes mellitus (GDM). CONCLUSIONS: We identified numerous studies that evaluated and supported the use of lifestyle interventions for women with GDM; however, there is a lack of research examining lifestyle interventions in pre-existing diabetes in pregnancy. FUNDING SOURCES: University of Leeds School of Food Science and Nutrition.