Rapid Fire Oral Presentation 49th Nutrition Society of Australia Annual Scientific Meeting 2025

The effect of body mass index and prebiotics supplementation on gestational diabetes mellitus (128054)

Rachelle Pretorius 1 2 , Summer Walker 2 , Susan Prescott 2 , Jeff Keelan 3 , Johan Garssen 4 , Thomas Sullivan 5 , Desiree Silba 2 , Debra Palmer 2
  1. School of Medical, Molecular and Forensic Sciences, murdoch university, Perth, Western Australia, Australia
  2. The Kids Research Institute, Nedlands, WA, Australia
  3. School of Medicine, The University of Western Australia, Perth, Western Australia, Australia
  4. Division of Pharmacology Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Utrech, The Netherlands
  5. SAHMRI Women and Kids, South Australian Health and Medical Research Institute, South Australia University, Adelaide, South Australia, Australia

Over recent decades, prebiotic fibre's immunomodulatory and anti-inflammatory activity has attracted the research community's attention. Prebiotics dietary supplementation has been found to improve glucose homeostasis in type 2 diabetes patients (1), likely mediated through microbial-derived short-chain fatty acid (SCFA) production (2). Nevertheless, evidence in human studies on prebiotic fibre intake during pregnancy on the prevention or treatment of gestational diabetes mellitus (GDM) is limited. Women who enter pregnancy overweight or obese (pre-pregnancy body mass index (BMI) ≥25 kg/m2 ) may be at increased risk of obesity-related comorbidities (including GDM) and a heightened risk of adverse birth outcomes for mother and child (3). The study aimed to determine whether pre-pregnancy BMI modifies the effect of prebiotics supplementation from mid-pregnancy on reducing the risk of GDM. We undertook a double-blinded, randomized controlled trial (RCT). Participants were women <21 weeks' gestation, non-smokers during pregnancy and not already consuming prebiotic supplements more than twice per week. The women (n = 652) were allocated to consume daily prebiotics (14.2 g of galacto-oligosaccharides (GOS) and fructo-oligosaccharides(FOS)) or placebo (8.7 g of maltodextrin) powder from 18-20 weeks' gestation. Subgroup analysis was performed to assess heterogeneity of the treatment effect of pre-pregnancy BMI on GDM diagnosis at 28 weeks of gestation. Overall, 288/652 (44.2%) women were classified as overweight/obese with a pre-pregnancy BMI ≥ 25 kg/m2, with 146/329 (44.4%) randomised to the prebiotics group and 142/323 (44.0%) in the placebo group. Pre-pregnancy BMI modified the effect of prebiotic supplementation, with the intervention reducing GDM rates in women with BMI ≥25 kg/m2 (prebiotics group 11.0% vs control group 21.8%; adjusted relative risk 0.50; 95% CI 0.28 to 0.89) but not BMI <25kg/m2 (7.7% vs. 4.4%; adjusted relative risk 1.72; 95% CI 0.70 to 4.19; interaction p = 0.02). Pre-pregnancy BMI was found to modify the effect of prebiotic supplementation on GDM rates, with benefit observed in overweight and obese women. Our results highlight a target population for future randomised controlled trials to investigate further the effects of prebiotics supplementation during pregnancy on gut modulation and reducing the risk of GDM.

1. Megur, A., Daliri, E. B., Baltriukienė, D., & Burokas, A. (2022). International journal of molecular sciences, 23(11), 6097

2. De Filippo C, Cavalieri D, Di Paola M.,  et al (2010)  Proc. Natl. Acad. Sci. 107 (33) 14691-14696

3. Poston L., Caleyachetty R., Cnattingius S., et al (2016) Lancet Diabetes Endocrinol 4 (12) 1025-1036