Biological control of vaginosis to improve reproductive health

Abstract The human vaginal microbiota plays an important role in the maintenance of a woman's health, as well as of her partner's and newborns'. When this predominantly Lactobacillus community is disrupted, decreased in abundance and replaced by different anaerobes, bacterial vaginosis (BV) may occur. BV is associated with ascending infections and obstetrical complications, such as chorioamnionitis and preterm delivery, as well as with urinary tract infections and sexually transmitted infections. In BV the overgrowth of anaerobes produces noxious substances like polyamines and other compounds that trigger the release of pro-inflammatory cytokines interleukin (IL)-1 β and IL-8. BV can profoundly affect, with different mechanisms, all the phases of a woman's life in relation to reproduction, before pregnancy, during fertilization, through and at the end of pregnancy. BV can directly affect fertility, since an ascending dissemination of the involved species may lead to tubal factor infertility. Moreover, the increased risk of acquiring sexually transmitted diseases contributes to damage to reproductive health. Exogenous strains of lactobacilli have been suggested as a means of re-establishing a normal healthy vaginal flora. Carefully selected probiotic strains can eliminate BV and also exert an antiviral effect, thus reducing viral load and preventing foetal and neonatal infection. The administration of beneficial microorganisms (probiotics) can aid recovery from infection and restore and maintain a healthy vaginal ecosystem, thus improving female health also in relation to reproductive health.