Antioxidant Supplementation for Management of Gestational Diabetes Mellitus in Pregnancy: A Systematic Review and Meta-Analysis of Randomised Controlled Trials

Abstract Purpose of Review Gestational diabetes mellitus (GDM) is the most common medical complication of pregnancy globally. Hyperglycaemia and associated production of reactive oxygen species can lead to oxidative stress in pregnancy. However, the potential effectiveness of increased antioxidant intake in the management of GDM has not been widely examined. Its usefulness alongside medical nutrition therapy (MNT) for assisting glycaemic control in women with GDM is poorly understood. This review aimed to establish the effect of antioxidant supplementation on the risk and management of gestational diabetes mellitus (GDM). Recent Findings A systematic review of intervention studies was conducted based on PRISMA guidelines. Databases searched were MEDLINE, CINAHL, Global Health, Scopus, Embase and Cochrane until September 2024. Random effects meta-analyses using Cochrane Review Manager software to establish the effect of antioxidant supplementation on glucose outcomes in women with GDM were conducted. A total of 13 studies (1380 participants) were included in the review with four different antioxidants used (selenium (n = 3); alpha-lipoic (n = 4); zinc (n = 5); e-3-gallate (n = 1)). Significant pre-post differences between antioxidant supplementation and control groups were found for fasting insulin (SMD, 95%CI) (-0.97 [-1.69 -0.24]; p = 0.009, HOMA-IR (-0.90 [-1.25, -0.54]; p < 0.0000, HOMA-B (-0.86 [-1.05, -0.67]; p < 0.00001 and QUICKI (1.09 [0.32,1.87]; p = 0.005 Heterogeneity was substantial (I2 > 50%, p < 0.05) for all models except for HOMA-B (I2 = 0%, p > 0.05). Summary Antioxidant supplementation has possible benefit as an adjunct therapy to current dietary management for women with GDM. Further clinical trials are needed to establish the preferred type and dosage of antioxidants likely to be effective.