Effects of Oral Probiotic Supplements on the Rate of Vaginal Colonization of Group B Streptococcus in Pregnant Women: A Clinical Trial Study

Background: Management of Group B Streptococcus (GBS) infection in a pregnant woman is one of the serious challenges for gynecologists and infectious disease specialists. The present clinical trial study aimed to investigate the impact of oral probiotic supplements on the rate of vaginal colonization of GBS in pregnant women. Methods: Overall, ۶۴ pregnant patients with vaginal GBS were selected to participate in this study. They were randomly divided into two groups (n=۳۲/each). The intervention group received a probiotic supplement capsule at a dose of ۵۰۰ mg daily for ۳۰ days, and the control group received a placebo for ۳۰ days. At the end of the study on day ۳۰, the vaginal sample was retaken with a sterile swab, and all the steps performed at the beginning of the study to diagnose GBS were repeated. Results: The average mean gestation at the first vaginal sampling was ۲۷.۰۹±۲.۴۸ weeks. There was no meaningful difference in age between the two groups of patients (P=۰.۴۷). Moreover, no considerable difference was found in the body mass index (P=۰.۳۷), weeks of gestation (P=۰.۹۲), or number of pregnancies (P=۰.۸۹) between the two groups. A significant relationship was observed between positive GBS and BMI in pregnant women (P=۰.۰۰۱), but this meaningful relationship was not found between GBS and age of patients (P=۰.۸۶) and age of pregnancy (P=۰.۱۶). Finally, there was no significant difference between the probiotic and placebo groups in terms of secondary test results for GBS (P=۰.۰۷). Conclusion: In the present study, oral probiotic supplementation did not significantly alter GBS in pregnant women, but for a definite opinion, a study with a larger sample size, different vaginal sampling techniques, a higher dose of oral probiotics, and an increase in the length of the intervention period is essential.