Recovery of Saccharomyces cerevisiae CNCM I-3856 in Vaginal Samples of Healthy Women after Oral Administration

Abstract

Bacterial vaginosis and vulvovaginal candidiasis are common causes of impaired health and quality of life for women. Although antimicrobial agents remain the main strategy for the treatment of vaginal infections, their repeated use involves high rates of resistance and recurrence. Alternative approaches such as probiotics are studied. Saccharomyces cerevisiae CNCM I-3856 already demonstrated beneficial effects in experimental models of vaginal infections. This randomized, double-blind, placebo-controlled clinical study was performed to evaluate the recovery of S. cerevisiae CNCM I-3856 in vaginal samples in healthy women after oral consumption. Sixty healthy women were randomized to receive a daily dose of S. cerevisiae CNCM I-3856 or a placebo for 4 weeks. Subcultures and quantitative polymerase chain reaction (qPCR) were used to detect the strain in vaginal and stool samples. A safety assessment was carried out throughout the study. Fifty-seven women completed the study. Over the 4-week supplementation phase, S. cerevisiae CNCM I-3856 has been detected in the vaginal samples of 21% of women (n = 4/19) in the 500 mg Probiotic group and 16% of women (n = 3/19) in the 1000 mg Probiotic group. The strain was detected in the faeces of 90% of women consuming the probiotic. This is the first clinical study demonstrating the migration of yeast from intestine to vagina where it may exert its benefits.

Keywords: Saccharomyces cerevisiae; microbiota; prevention; probiotic; vaginal health; vaginal infection; yeasts.

Figure 1

Experimental design of the clinical study (this diagram presents the study timeline (days, D) and the visits (V). For example, V1 corresponds to the randomization visit planned at D0 which is the first day of the supplementation phase).

Figure 2

Clinical study diagram according to Consolidated Standards of Reporting Trials (CONSORT) guidelines.

Figure 3

Proportion of women (%) with S. cerevisiae CNCM I-3856 detected in vaginal samples at each study timepoint (n = 19 for Probiotic 500 mg group, n = 19 for Probiotic 1000 mg group and n = 19 for placebo group).

Figure 4

Proportion of women (%) with S. cerevisiae CNCM I-3856 detected in stool samples at each study timepoints (n = 19 for Probiotic 500 mg group, n = 19 for 1000 mg group and n = 19 for placebo group).

Figure 5

Estimated CFU counts of S. cerevisiae CNCM I-3856 detected in stool samples at each study timepoint expressed as log10 CFU/sample. Only the samples in which the yeast was detected are figured in this plot.