Application of Lactobacillus Salivarius CECT5713 in Infertility of Unknown Origin
Condition: Abortion, Spontaneous; Abortion in First Trimester; Infertility Unexplained
MeSH terms: Infertility; Abortion, Spontaneous
Study type: Interventional
Phase: Phase 2

Summary: 
      In this study, we aimed to assess the cervicovaginal environment (pH, Nugent score, soluble
      immune factors and bacterial profile) in women with reproductive failure because of either
      repetitive abortion or infertility of unknown origin and compare it to that of healthy
      fertile women. The second objective was to evaluate the ability of Lactobacillus salivarius
      CECT5713 to modulate such parameters and to increase pregnancy rates in women with
      reproductive failure. The administration of L. salivarius CECT5713 (~9 log10 colony-forming
      units (CFU)/day) for 6 months or until a diagnosis of pregnancy to women with reproductive
      failure resulted in an overall successful (term) pregnancy rate of 56%.
    

Detailed description: 
      In this study, we aimed to assess the cervicovaginal environment (pH, Nugent score, soluble
      immune factors and bacterial profile) in women with reproductive failure because of either
      repetitive abortion or infertility of unknown origin and compare it to that of healthy
      fertile women. The second objective was to evaluate the ability of Lactobacillus salivarius
      CECT5713 to modulate such parameters and to increase pregnancy rates in women with
      reproductive failure. Vaginal pH and Nugent score were higher in women with reproductive
      failure than in fertile women. Differences were also noted regarding soluble immune factors
      transforming growth factor beta (TGF-β) and vascular endothelial growth factor (VEGF). Their
      concentrations in cervicovaginal lavage samples were reduced by about one-half in women with
      reproductive failure compared to fertile women. Lactobacilli were detected in a higher
      proportion, and at a higher concentration and having different species profile, in fertile
      women than in women with repetitive abortion or infertility. The study of the vaginal
      microbiome revealed that samples from fertile women were characterized by the high abundance
      of Lactobacillus sequences, while in about one third of samples from women with reproductive
      failure DNA from this genus was practically absent while there was an abundance of that of
      Gardnerella and Bifidobacterium. Lactobacillus salivarius CECT5713 seemed to be a suitable
      candidate to modulate the cervicovaginal microbiota because of its acidifying capacity,
      adhesion to vaginal cells and co-aggregation with vaginal pathogens. The administration of L.
      salivarius CECT5713 (~9 log10 CFU/day) for 6 months or until a diagnosis of pregnancy to
      women with reproductive failure resulted in an overall successful (term) pregnancy rate of
      56%. In addition, the probiotic intervention modified significantly key microbiological,
      biochemical and immunological parameters in women who got pregnant being their
      post-intervention values similar or close to those of fertile women. The high concentrations
      of L. salivarius and the detection of L. salivarius DNA in vaginal samples confirmed that the
      probiotic was able to reach the vaginal mucosa. In conclusion, L. salivarius CECT5713 has
      proved to be a good candidate to improve reproductive success in women with reproductive
      failure.
    

Intervention name(s): Lactobacillus salivarius CECT5713
Intervention type(s): Biological
Intervention description(s): Starting at day 0, women of the RA and INF groups consumed (oral route) a daily sachet with ~50 mg of freeze-dried probiotic (~9 log10 CFU of L. salivarius CECT5713) for 6 months or until a diagnosis of pregnancy (whatever happened first).
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Intervention model description: Volunteers were classified into 3 groups. All women in the RA group (n = 21) had a history of recurrent miscarriage with three or more pregnancy losses during the first 12 weeks of pregnancy. All women of the INF group (n = 23) had a history of infertility (inability to conceive) despite being the recipients of assisted-reproduction techniques (ART) for at least three times, including two cycles, at least, of in vitro fertilization (IVF). Finally, the control group (n = 14) included fertile women having at least two children after uncomplicated term pregnancies. Starting at day 0, women of the RA and INF groups consumed (oral route) a daily sachet with ~50 mg of freeze-dried probiotic (~9 log10 CFU of L. salivarius CECT5713) for 6 months or until a diagnosis of pregnancy (whatever happened first).
Masking: None (Open Label)
Primary purpose: Basic Science
Keywords: Infertility; Abortion