Oral Lacticaseibacillus rhamnosus GG Exposure During Pregnancy and Effects on Maternal Inflammatory Response—A Blinded, Pilot Randomized, Placebo-Controlled Study

Journal article, 2025

Problem: This study aimed to investigate whether Lacticaseibacillus rhamnosus GG intake during pregnancy influences maternal cytokine levels and lymphocyte subpopulations. Method: Pregnant women were categorized into three groups: those with a history of spontaneous preterm delivery (PTD) (n = 40), those with a history of preeclampsia (n = 40), and nulliparous or parous women without a history of PTD or preeclampsia (n = 40). Participants were randomized to receive either L. rhamnosus GG or a placebo. Maternal blood samples were collected at baseline before gestational week 19 (visit 1) and around gestational weeks 25 and 35 (visits 2 and 3). The primary outcome was the change in tumor necrosis factor-alpha (TNF-α) levels in monocytes after stimulation of maternal blood with Escherichia coli lipopolysaccharide (LPS). Secondary outcomes included lymphocyte subpopulation analysis and changes in TNF-α, interleukin (IL)-10, and IL-12 levels after stimulation with E. coli LPS, Lactobacillus paracasei, or Pseudomonas aeruginosa. Results: In the intention-to-treat analysis, no significant differences in TNF-α levels were observed. However, a sensitivity analysis excluding participants with fever or recent antibiotic use (n = 27) revealed a significant decrease in TNF-α levels in the intervention group at visit 2 compared to an increase in the placebo group (mean difference −11785 cells/mL, 95% CI: −22459 to −1287, p = 0.03). Secondary analyses showed lower total lymphocyte, T-cell, IL-10, and IL-12 levels at visit 2 and higher IL-10 and IL-12 levels at visit 3 in the intervention group. Conclusions: Although L. rhamnosus GG did not significantly affect TNF-α levels, its influence on lymphocyte and cytokine levels warrants further investigation through larger trials.