The role of Lactobacillus iners and bacterial vaginosis-associated microorganisms in making up the vaginal microbiota

Mikhanoshina N.V., Priputnevich T.V., Bairamova G.R.

Academician V.I. Kulakov National Medical Research Center of Obstetrics, Gynecology, and Perinatology, Ministry of Health of Russia, Moscow, Russia
Objective: To summarize the data available in the literature on the currently used criteria for evaluating the vaginal microbiota in reproductive-aged women, the principles of its classification, and the exogenous and endogenous factors influencing the microbial structure. The review includes data from the publications presented in the MedLine and Russian Science Citation databases. The review describes the key distinguishing features of the species Lactobacillus iners from other vaginal lactobacillus species, including cultivation features, tinctorial properties, and pathogenicity power. It presents data on the frequency of this species in the microbiota of reproductive-aged women and elucidates the need for its isolation and identification in the microbiological laboratories of any level in order to make a correct diagnosis. There are data on the characteristics of the vaginal microbiota in bacterial vaginosis, which are due to a variety of the microflora, including the species diversity of Gardnerella spp. The review highlights the role of a polymicrobial biofilm in the pathogenesis of bacterial vaginosis. It touches upon the relevance of a further study of the interaction of Gardnerella spp. and L. iners species, as well as the effectiveness of an integrated approach to evaluating the vaginal microbiota, by using the results of classical and molecular biological methods.
Conclusion: L. iners is one of the most common lactobacilli in the microbiota of reproductive-aged women. The role of this species in the functional stability of the vaginal microbiota has not yet been defined to date. Further investigation of the species is required to establish strain diversity. There is a need for routine practice introduction of research methods allowing the isolation of L. iners in the microbiological laboratories of all levels.

Authors’ contributions: Mikhanoshina N.V., Priputnevich T.V., Bairamova G.R. – concept and design of the investigation; Mikhanoshina N.V. – material collection and processing, writing the text; Priputnevich T.V., Bairamova G.R. – editing.
Conflicts of interest: The authors declare that there are no conflicts of interest.
Funding: The article has been prepared without financial support
For citation: Mikhanoshina N.V., Priputnevich T.V., Bairamova G.R.
The role of Lactobacillus iners and bacterial vaginosis-associated microorganisms
in making up the vaginal microbiota.
Akusherstvo i Ginekologiya/Obstetrics and Gynecology. 2023; 1: 20-26 (in Russian)


vaginal microbiota
Lactobacillus iners
bacterial vaginosis


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Received 13.10.2022

Accepted 06.12.2022

About the Authors

Natalya V. Mikhanoshina, bacteriologist, Head of Biomaterials Collection and Storage Laboratory, Institute of Microbiology, Antimicrobial Therapy and Epidemiology,
V.I. Kulakov NMRC for OG&P, Ministry of Health of Russia, +7(916)546-47-80,,,
117997, Russia, Moscow, Akademika Oparina str., 4.
Tatiana V. Priputnevich, Corresponding Member of the RAS, Dr. Med. Sci., Director of the Institute of Microbiology, Antimicrobial Therapy and Epidemiology, V.I. Kulakov NMRC for OG&P, Ministry of Health of Russia, +7(910)414-56-16,,,
117997, Russia, Moscow, Akademika Oparina str., 4.
Guldana R. Bairamova, Dr. Med. Sci., Professor at the Department of Obstetrics and Gynecology of the Department of Professional Education, Head of Clinical Work of the Scientific Polyclinic Department, V.I. Kulakov NMRC for OG&P, Ministry of Health of Russia, +7(495) 438-18-66 (ex. 1489),,, 117997, Russia, Moscow, Akademika Oparina str., 4.
Corresponding author: Natalya V. Mikhanoshina,

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