The vaginal microbiota plays a key role in women’s intimate health. This complex ecosystem, consisting mainly of bacteria – lactic acid bacteria – is responsible for maintaining microbiological balance and protection against pathogens.
Disturbances in the microflora and lack of dominance of lactic acid bacteria in the vagina lead to dysbiosis, which paves the way for other microorganisms, e.g. streptococci, staphylococci, Candida fungi or protozoa (trichomoniasis vaginalis) to excessive growth. Vaginal dysbiosis may be asymptomatic, but its most common symptoms include vaginal discharge, itching and burning, or an unpleasant odor. It may have consequences such as pelvic inflammatory disease, infertility, miscarriage, premature rupture of membranes and premature delivery (Gudnadottir et al., 2022).
An innovative solution in the prevention and treatment of vaginal dysbiosis are postbiotics – bioactive metabolites produced by probiotics that can modulate the vaginal microbiota, supporting its balance and health.
The importance of vaginal microbiota
The vaginal microbiota is a natural bacterial ecosystem dominated by lactic acid bacteria of the Lactobacillus genus. Their presence is crucial for maintaining an acidic pH (3.8–4.5), which inhibits the development of pathogens such as Candida albicans, Escherichia coli and Gardnerella vaginalis. This protective barrier is sensitive to hormonal changes, antibiotics, poor hygiene and stress. When the balance of microflora is disturbed, there is a risk of intimate infections, such as bacterial vaginosis or vaginal mycosis (Plummer, Vodstrcil, & Bradshaw, 2024).
Bacterial species Lactobacillus spp. develop in the anaerobic vaginal environment and produce postbiotics (metabolites), such as organic acids (including lactic acid), hydrogen peroxide (H2O2), and bacteriocins. Lactic acid bacteria thus contribute to maintaining a healthy vaginal microbiome and have a defensive function against pathogenic strains. L-lactic and d-lactic acid maintains the pH value of the vaginal environment at a level lower than 4.5 and significantly reduces the risk of developing infection with pathogenic bacteria or fungi that require higher pH conditions to grow. The low acidic pH of the environment also favors re-colonization by Lactobacillus bacteria. Vaginal pH also depends on the amount of glycogen stored in the vaginal epithelial cells, which is processed by Lactobacillus bacteria into lactic acid. The production of organic acids promotes the adhesion of bacteria of the Lactobacillus genus to the vaginal epithelium and allows maintaining its proper microflora in terms of quantity and quality. Lactic acid also has properties that damage the cell membranes of some bacteria and fungi, which leads to leakage of cytoplasm from the damaged cell and, consequently, to its death. Most scientific data also support the theory regarding the protective role of H2O2 against dysbiosis and pathogen colonization. An important element of the lactic acid bacteria metabolite are also antibacterial bacteriocins, which have the ability to degrade DNA or rRNA of potentially pathogenic microorganisms. Bacteriocins are very biologically powerful – it is assumed that one molecule kills one sensitive bacterial cell. The most important of them are acidolin, lactacin, amylovirin, lactobin and plantaricin (O’Hanlon, Moench, & Cone, 2011; Witkin & Linhares, 2017).
What are postbiotics?
Postbiotics are bioactive metabolites produced by probiotic bacteria during fermentation processes. They include, among others: short chain fatty acids, exopolysaccharides, bacteriocins and enzymes. Unlike probiotics, which contain live microorganisms, postbiotics are products of their activity and do not contain live bacteria. This makes them more stable, easier to store and safer for people with weakened immune systems.
Properties of postbiotics
- Regulation of vaginal pH – Lactic acid contained in postbiotics helps maintain an acidic vaginal environment, which favors the growth of beneficial bacteria;
- Antibacterial and antifungal effects – Compounds such as bacteriocins inhibit the growth of pathogens, including Candida albicans and Escherichia coli;
- Stimulation of the immune system – Postbiotics enhance the local immune response, which helps fight infections;
- Blocking the biofilm – The biofilm created by pathogens makes it difficult to eliminate them. Postbiotics prevent its formation, which facilitates the treatment of the infection.
Prevention and therapy of urogenital infections using postbiotics
Postbiotics are used in the prevention of intimate health, especially in women at risk of recurrent vaginal infections. Vaginal gels or creams containing postbiotics support the development of lactic acid bacteria, inhibiting the multiplication of pathogens.
Regular use of postbiotic products brings numerous benefits, including:
- Protection against bacterial and fungal infections
- Reduction of symptoms such as itching, burning and vaginal dryness
- Restoring the natural pH of the vagina
A healthy vaginal microflora is important in the prevention of diseases of the entire urogenital system. A dysbiotic vaginal environment may be a potential reservoir for intestinal bacteria that can migrate to the urinary tract. The vagina is also an important site for interventions aimed at supporting the vaginal microbiota and reducing the risk of urinary tract infections.
Postbiotics can be used not only for prevention, but also for the treatment of intimate infections. In combination with antibiotics or as a stand-alone therapy, postbiotic products reduce the risk of recurrence of infections and support the reconstruction of vaginal microflora.
Clinical studies by Shen et al et al. (2023) showed that postbiotic gels effectively alleviate the symptoms of bacterial vaginal infection.
Products containing lactic acid bacteria metabolites also have the ability to inhibit the growth of pathogens by blocking the bacterial biofilm and promoting colonization by lactic acid bacteria (O’Hanlon et al., 2011). This action allows for faster and more effective fight against infection, and at the same time minimizes the risk of recurrence.
Safety and tolerability of postbiotics
Postbiotics are well tolerated by the body and have a high safety profile. In clinical trials, postbiotic-based products were effective and free from serious side effects (O’Hanlon et al., 2011; Shen et al., 2023).
Summary
Postbiotics are the future in the prevention and therapy of intimate infections. Their ability to modulate the vaginal microbiota, support its balance and protect against pathogens makes them an effective and safe tool in caring for women’s intimate health. Products containing postbiotics already offer patients innovative solutions that can revolutionize the approach to vaginal health. In the face of the growing number of intimate infections and problems related to antibiotic therapy, postbiotics offer natural, effective and safe support for intimate health.
Gudnadottir, U., Debelius, J. W., Du, J., Hugerth, L. W., Danielsson, H., Schuppe-Koistinen, I., . . . Brusselaers, N. (2022). The vaginal microbiome and the risk of preterm birth: a systematic review and network meta-analysis. Sci Rep, 12(1), 7926. doi:10.1038/s41598-022-12007-9
O’Hanlon, D. E., Moench, T. R., & Cone, R. A. (2011). In vaginal fluid, bacteria associated with bacterial vaginosis can be suppressed with lactic acid but not hydrogen peroxide. BMC Infect Dis, 11, 200. doi:10.1186/1471-2334-11-200
Plummer, E. L., Vodstrcil, L. A., & Bradshaw, C. S. (2024). Unravelling the vaginal microbiome, impact on health and disease. Curr Opin Obstet Gynecol, 36(5), 338-344. doi:10.1097/GCO.0000000000000976
Shen, X., Xu, L., Zhang, Z., Yang, Y., Li, P., Ma, T., . . . Sun, Z. (2023). Postbiotic gel relieves clinical symptoms of bacterial vaginitis by regulating the vaginal microbiota. Front Cell Infect Microbiol, 13, 1114364. doi:10.3389/fcimb.2023.1114364
Witkin, S. S., & Linhares, I. M. (2017). Why do lactobacilli dominate the human vaginal microbiota? BJOG, 124(4), 606-611. doi:10.1111/1471-0528.14390
