The Basics

  • The vaginal microbiota (VMB) is the collection of microbes (bacteria, fungi, archaea, viruses, protists) that live in your vagina. These microbes play a large role in maintaining vaginal health and preventing (or promoting) infections.

  • When the vaginal microbiota gets out of balance, this is considered dysbiosis. Dysbiosis can present as many different conditions (bacterial vaginosis, aerobic vaginitis, yeast infections, UTIs), but they often have similar symptoms. Dysbiosis is linked to pre-term birth, infertility, increased STI risk, cancer, pain, inflammation (vaginitis), and more.

  • A healthy composition of vaginal microbiota consists primarily of Lactobacilli species. Specifically, Lactobacillus crispatus is thought to be the most protective; it produces lactic acid, which maintains a healthy pH, and secretes bacteriocins, which suppress unwelcome and pathogenic anaerobes (like the ones that proliferate in bacterial vaginosis). Currently, the vaginal microbiota can be characterized into one of five community state types (CSTs), depending on which strain of Lactobacillus is dominant (or if the microbiome lacks Lactobacilli). Vaginal microbiotas that are not dominated by Lactobacilli, and are instead microbially diverse, are considered less stable; they are dysbiotic and prone to inflammation and infection.

  • The best way to know what is going on in your vaginal microbiome is to take a metagenomics test. This type of genetic sequencing can give you a complete breakdown of what microbes are present in your vagina.

  • With our vaginal microbiota transplants, a small amount of vaginal fluid from a healthy donor is inserted into the vagina of a recipient via an at-home, single-use vaginal applicator. This transfers the entire ecosystem of a healthy vagina (primarily beneficial organisms, as well as other components and metabolites) to the recipient’s vagina. The transfer of the eubiotic (balanced) ecosystem promotes the growth of healthy microbes and suppresses bad ones. Prior to donation, healthy donors are screened for STIs, and their vaginal microbiomes are sequenced to confirm Lactobacilli dominance.

Key Takeaways

  • A healthy vagina contains mostly L. crispatus

  • L. crispatus is protective against BV- and dysbiosis-associated bacteria

  • Increased microbial diversity —> microbial imbalance —> vaginal dysbiosis

  • BV and vaginal dysbiosis are linked to increased STI transmission, infertility, and pre-term birth

  • Restoring Lactobacillus spp. can return the vaginal microbiome to a healthy, stable state and reduce the presence of unwanted dysbiosis-associated microbes

Vaginal microbiota transplantation is a truly opulent & promising edge: fully grasp its potential

Yiming Meng, Jing Sun, Guirong Zhang. Front Cell Infect Microbiol (2024).

Figure 1 Harnessing beneficial vaginal microbiota transplantation (VMT) to Restore vaginal microbiota and combat bacterial vaginosis (BV). The purpose of the transplantation is to restore the harmonious equilibrium of the vaginal microbiota, which is often disturbed in cases of BV. This method presents a hopeful pathway for addressing this prevalent ailment by harnessing the potency of advantageous microorganisms to fight the detrimental ones: H2O2 has been enhanced; competition for nutrition has increased. Additionally, there has been an improvement in the capacity of epithelial cells to adhere, and the presence of Lactobacillus is abundant. The pH level is low, creating a functional and protective barrier.

Figure 2 Restoring a healthy microbiota for improved therapy efficacy in cervical cancer. VMT has the potential to contribute to cervical cancer treatment via many channels. Restoring a healthy microbiota by VMT has the potential to improve the local immune response, leading to better elimination of HPV and lowering the likelihood of HPV persisting and progressing to cervical cancer. Furthermore, altering the composition of the vaginal microbiota has the potential to impact the effectiveness of therapy for cervical cancer. (All figures were drawn by FigDraw).

What the Experts Are Saying

“If we can optimize the vaginal microbiome in a sustainable way, then we could potentially address the sequelae of dysbiosis, including HIV acquisition, preterm birth, and potentially other indications as well.”

— Craig Cohen, MD, University of California, San Francisco

“Crispatus is the golden child of all the lactobaccilli.”

— Melissa Herbst-Kralovetz, PhD, University of Arizona

“After fecal microbiota transplantation, it sort of seems logical that if transferring a whole microbiome works in one condition, it might work in another.”

— Caroline Mitchell, MD, Massachusetts General Hospital

Resources to Learn More

Companies

  • Vaginal Biome Science

    a biotech company focused on vaginal microbiota-based therapies & increased education & collaboration

  • Evvy Vaginal Microbiome Test

    female-founded company promoting precision medicine with metagenomic sequencing of vaginal microbiomes

  • Freya Biosciences

    clinical-stage company designing microbial immunotherapies to treat infertility

Even More Links & Articles

Articles