The effect of oral probiotics on glycemic control of women with gestational diabetes mellitus—a multicenter, randomized, double-blind, placebo-controlled trial

Gestational diabetes mellitus should be treated adequately to avoid maternal hyperglycemia-related complications. Previously, probiotic supplements were suggested to improve fasting blood glucose in women with gestational diabetes mellitus. However, a major limitation of previous studies was that preprandial and especially postprandial glucose values, which are important predictors of pregnancy outcomes, were not studied.This study aimed to examine the effect of a mixture of probiotic strains on maternal glycemic parameters, particularly preprandial and postprandial glucose values and pregnancy outcomes among women with gestational diabetes mellitus.A multicenter prospective randomized, double-blind, placebo-controlled trial was conducted. Women newly diagnosed with gestational diabetes mellitus were randomly allocated into a research group, receiving 2 capsules of oral probiotic formula containing Bifidobacterium bifidum, B lactis, Lactobacillus acidophilus, L paracasei, L rhamnosus, and Streptococcus thermophilus (>6 × 109/capsule), and a control group, receiving a placebo (2 capsules/day) until delivery. Glycemic control was evaluated by daily glucose charts. After 2 weeks, pharmacotherapy was started in case of poor glycemic control. The primary outcomes were the rate of women requiring medications for glycemic control and mean daily glucose charts after 2 weeks of treatment with the study products.Forty-one and 44 women were analyzed in the treatment and placebo cohorts, respectively. Mean daily glucose during the first 2 weeks in the probiotics and placebo groups was 99.7±7.9 and 98.0±9.3 mg/dL, respectively (P=.35). The rate of women needing pharmacotherapy because of poor glycemic control after 2 weeks of treatment in the probiotics and placebo groups was 24 (59%) and 18 (41%), respectively (P=.10). Mean preprandial and postprandial glucose levels throughout the study period were similar between the groups (P>.05). There were no differences in maternal and neonatal outcomes, including birthweight and adverse effect profile between the groups.The oral probiotic product tested in this study did not affect glycemic control of women with gestational diabetes mellitus.