Much of the current literature has investigated the potential of probiotics in preventing of bacterial vaginosis and preterm labor, but the usefulness of using probiotics as a surrogate or adjunctive therapy for intra-partum antibiotics prophylaxis in GBS colonized pregnant women dose not have any. This is the first study to investigate the role of probiotics in preventing and treating vaginal colonization by GBS in pregnant women. The purpose of this study is to examine whether oral taking Latobacillus-containing probiotics can reduce the GBS colonization rate of vagina and rectum in pregnant women who present with GBS-positive. Through the results of our study, we try to investigate the role of probiotics in preventing the unnecessary tests, admission and antibiotic treatment in newborn with GBS-positive mother who deliver fewer than 4 hours after laboring. We hope our results may have some effects on GBS sepsis protocols.