A randomized controlled trial of probiotics to reduce maternal glycaemia in obese pregnancy

OBJECTIVE: Probiotics are live microorganisms which may confer health benefits on the host. They have a potential role in pregnancy for improving maternal glycaemic control and insulin resistance. Obese pregnant women are at high risk of adverse metabolic outcomes but little is known of the effects of probiotics in this population group. The aim of this study was to investigate the effects of a probiotic capsule on maternal fasting glucose and other metabolic indices in obese pregnancy. STUDY DESIGN: This was a double‐blinded placebo‐controlled randomized trial of 138 pregnant women with a body mass index (BMI) of 30.0‐39.9kg/m2. Women were randomized to either a probiotic (Lactobacillus salivarius UCC118) or a placebo capsule once daily from 24 to 28 week's gestation. Blood samples were collected pre and post the 4 week intervention. The primary outcome was a reduction in fasting glucose and secondary outcomes were changes in insulin, C‐peptide, HOMA, lipids and CRP. A sample size of 100 was required to detect a difference in fasting glucose of 0.4 with 80% power at the 0.05 level of significance. RESULTS: Twenty‐eight women were excluded from analyses due to antibiotic use and poor capsule compliance (missed >2 capsules), resulting in a total of 110 subjects for final analysis. BMI was the only maternal factor that differed between the groups at baseline (32.9±2.6 probiotic vs 34.0±2.7kg/m2 placebo, p=0.044) and this was controlled for in subsequent analyses. No significant differences in fasting glucose, insulin, HOMA index, C‐peptide, total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides or CRP were detected between the groups post‐intervention. Gestational weight gain, rate of gestational diabetes and birth weight also did not differ significantly between the two groups. CONCLUSION: While previous studies of probiotics in healthy pregnant women showed some beneficial glycaemic effect, this randomized trial demonstrated no impact on fasting glucose or on markers of metabolic health in obese pregnancy. (Table presented).