Effects of probiotic supplements on insulin resistance in gestational diabetes mellitus: A double‐blind randomized controlled trial

Double-blind, randomized, placebo-controlled trial conducted June 2016–February 2017 at Ramathibodi Hospital, Bangkok, Thailand. Participants: 60 pregnant women with diet-controlled gestational diabetes mellitus diagnosed at 24–28 weeks gestation; singleton pregnancies; aged 18–45 years; no history of chronic diseases.

One probiotic capsule daily after the morning meal for four weeks; each capsule contains 1 x 10^9 CFU Lactobacillus acidophilus and 1 x 10^9 CFU Bifidobacterium bifidum; refrigerate at 4°C.

Probiotic supplementation for four weeks significantly improved glucose metabolism vs placebo: fasting plasma glucose changes -3.94 mg/dL (95% CI -7.62 to -0.27; P=0.03); fasting insulin changes -2.67 mIU/L (95% CI -3.57 to -1.76; P=0.01); HOMA-IR changes -0.63 (95% CI -0.86 to -0.41; P=0.01). Weight gain and caloric intake were similar between groups; neonatal outcomes were not significantly different. Conclusion: four weeks of probiotic supplements lowered fasting glucose and increased insulin sensitivity in diet-controlled GDM and may be considered as an adjunct treatment for glycemic control.

Small sample size (n=60); short duration (4 weeks); single-center Thai population; not powered to assess pregnancy outcomes; no data on gut microbiota composition, GLP-1, or short-chain fatty acids.