Dominant Lactobacillus spp. in different conditions of vaginal microbiocenosis

The vaginal microbiota is a primary non-specific barrier that protects against various bacterial, viral and fungal pathogens. A normal microflora of the female genital tract is represented by aerobes, facultative and strict anaerobes. Bacteria of the genus Lactobacillus spp. dominate the majority of women of reproductive age. They have high protective properties against other microorganisms. Lactobacillus spp. prevent an excessive reproduction of opportunistic and pathogenic microorganisms in the vaginal biotope due to the synthesis of short-chain acids that maintain the pH value in the normal range. As a rule, one or two species of Lactobacillus spp. dominate in the vaginal biotope, which are responsible for ensuring homeostasis of the vaginal microflora. At the same time, various Lactobacillus spp. differ in their protective properties. L. crispatus is a marker of the stability of the vaginal microflora. With the dominance of this type of lactobacillus, the authors of the studies observed a low risk of bacterial vaginosis, aerobic vaginitis, and unwanted obstetric complications during pregnancy and in assisted reproductive technology protocols, as well as a reduced risk of infection with sexually transmitted infections and human papillomavirus. L. gasseri and L. iners were more often detected in women with intermediate microflora or with dysbiosis. L. iners, unlike L. crispatus, has reduced protective properties and is widespread in dysbiotic conditions of the vaginal microflora. The detection of L. iners can serve as a prognostic sign of the development of pathological conditions of the vaginal microflora.