 The power for the present study was calculated using the dichotomized endpoint: recovery yn. i.e., defined as GBS negative. For the sample size calculation, the investigators assume that 43 of the women in the verum group will achieve the primary endpoint i.e., recovery to the GBS negative state. This calculation is based on previously published clinical and preclinical data 18-20. The investigators expect a 18 recovery rate in the placebo group. Under these assumptions, the Chi-Squared test at two-sided significance level α 0.05 will have 90 power to detect the group difference in a sample of N 70 per group. With regard to a drop-out rate of 10, the investigators will therefore need to screen N 1040 at study visit 1, which would lead to 6241040 60 patients without infection, of which 156624 25 will be GBS-positive. Out of these, N 78 per group will then be randomized, which would lead to N 70 per group after the estimated drop-out of 10. The investigators will need between 9-12 months to screen 1040 patients for study inclusion. 