The effect of probiotic supplementation on the risk of gestational diabetes mellitus among high-risk pregnant women: A parallel double-blind, randomized, placebo-controlled clinical trial

Background: Based on a comprehensive search, we realized that the findings of the available literature are contradictory, and also limited data are available on Middle Eastern populations in terms of probiotic supplementation during the pregnancy. Therefore, the current double-blind, randomized, placebo-controlled clinical trial was carried out to investigate the effects of probiotic supplementation during pregnancy on the risk of gestational diabetes mellitus and also other maternal and neonatal outcomes. Materials and methods: The pregnant women were randomized to either received probiotic supplement (n = 271) or placebo (n = 271) from the first half of the second trimester (14 weeks of pregnancy) up to 24 weeks when pregnant women routinely evaluated regarding the GDM. During the 24-28 weeks of pregnancy, mothers were evaluated regarding the presence of GDM using a 75 g oral glucose tolerance test (OGTT). The fasting blood glucose (FBG) was also evaluated within OGTT processes. Each 500 mg probiotic capsule was a mixture of Lactobacillus acidophilus LA1 (>7.5 x 109 CFU), Bifidobacterium longum sp54 cs (>1.5 x 109 CFU), and Bifidobacterium bifidum sp9 cs (>6 x 109 CFU). Results: Overall, 507 pregnant women make up our study population with a mean age of 32.03 years and a Body Mass Index (BMI) of 30.20 kg/m2. There was no significant difference between the intervention and the control group regarding FBG (88.68 vs. 89.61 mg/dL; P = 0.338), OGTT-1h (163.86 vs. 166.88; mg/dL; P = 0.116), and OGTT-2h (138.39 vs. 139.27; mg/dL; P = 0.599). The incidence of GDM in the intervention group was 41.9% which was not significantly different from the control group (40.2%) (P = 0.780). Likewise, no significant difference was detected in terms of other studied parameters. Conclusions: It seems that probiotics supplementation of pregnant women from the first half of the second trimester up to 24 weeks of pregnancy does not reduce the risk of GDM, or improve other neonatal and maternal outcomes.