 In case of a negative GBS screening result, women will be excluded from the study. In case of a positive GBS screening result, women will be randomized to the verum or the placebo group. The study will follow a prospective randomized placebo-controlled double-blinded mono-centric design. Randomization will be performed using Randomizer Institute for Medical Informatics, Statistics and Documentation, Medical University of Graz, which is a web-based patient randomization service for clinical trials. Women who are assigned to the verum group will receive a patented dietary supplement of four viable lactobacilli strains Astarte, Pizeta Pharma S.p.a., Ponte San Giovanni, Italy, containing Lactobacillus crispatus Lbv88, Lactobacillus rhamnosus Lbv96, Lactobacillus jensenii Lbv116, and Lactobacillus gasseri Lbv150. This supplementation was proven to transmigrate from the intestinal lumen into the vaginal area, acting in the microbial ecosystem through a barrier effect against pathogenic microorganisms, so that symptoms related to dysbiosis and recurrent infections can be relieved or even prevented 14-16. Supplementation will include twice daily morningevening oral intake for 14 days. Women in the placebo group will receive an identical-looking oral potato-maltodextrin-based placebo, which will also be given twice daily morningevening for 14 days. Patients, investigators, and microbiological staff will be blinded to the treatment assignment. The composition of the study medication is as follows: L.crispatus Lbv88 DSM 22566 1 x 109 Guaranteed viable cell count CFUdose, L. rhamnosus Lbv96 DSM 22560 1 x 109 CFUdose, L. jensenii Lbv116 DSM 22567 0.2 x 109 CFUdose, L. gasseri Lbv150N DSM 22583 0.3 x 109 CFUdose, Potato maltodextrin, Insoluble dietary fibre, and Silicium dioxide. 