From mother to employee to wife, women are very dynamic. The vaginal microbiota that comprises their reproductive organs is just as much so. While research on the vaginal microbiome is in its infancy (pun sort of intended), all scientific evidence alludes to one thing. The relative abundance of Lactobacillus species within the vaginal microbiome heavily dictates women’s health. Just as women are dynamic, so are the various Lactobacillus species (and other microbes). That’s why vaginal health is broken down into five general vaginal community state types.
What is the vaginal microbiome?
Before jumping into vaginal community state types (CSTs), let’s dive into a crash course about the vaginal microbiome. The vaginal microbiome is a name to collectively describe the various microscopic beings living around the vagina.
The majority of bacteria that comprise vaginal microbial communities are of the Lactobacillus species . Lactobacilli regulate the vaginal pH, making it inhospitable for most other anaerobic bacteria and microbes to successfully attempt vaginal colonization.
Vaginal Lactobacilli: Key role in health
The relevance of the vaginal microbiota plays a significant function in women’s health. Having a predominance of a specific Lactobacillus species is a good predictive indicator of the vaginal health of a person.
Various Lactobacilli play a protective role to their host, which is you! The key role of this microbial network is to maintain the pH balance of the human vagina.
The goal of vaginal bacteria is to keep levels between 3.4 and 4.5 . That sweet spot makes it very challenging for opportunistic pathogens to disrupt a healthy vaginal bacterial community composition. Through this regulation, Lactobacilli act as local immune mediators.
Lactobacilli accomplishes this goal by producing lactic acid. Between these acidic levels and the presence of Lactobacilli, a healthy vaginal microbiome plays the ultimate defense game in Red Rover. Opportunistic pathogens that promote inflammatory cytokines can’t break through and wreak the havoc they desire!
Having a dominant Lactobacilli species can improve various vaginal complaints, including:
• Aerobic vaginitis (AV) 
• Preterm birth 
• Pelvic inflammatory diseases (PID) 
• Recurrent yeast infections 
• Recurrent urinary tract infections (UTIs) 
• Skin irritations, itching, and burning 
• Painful sex 
There are 170 known Lactobacillus spp . However, just a handful is the most dominant vaginal Lactobacilli. While they all fall under the same genus, these species have unique traits.
Therefore, they can create an environment conducive to different bacterial communities. These variations in vaginal commensal microorganisms might cause a local immune response or other vaginal complaints. It can also leave the vaginal microbiome susceptible to opportunistic pathogens.
Why a microbiome assessment for the human vagina important
According to the Centers for Disease Control (CDC), 84% of women with an imbalance within the vaginal microbiome are asymptomatic . These knowledge gaps can cause long-term problems, such as PID. PID can result in reproduction issues or cervical cancer.
That’s why it’s so important for women to get a yearly examination from their doctor. Please take note of any changes in sensations, odors, and recurrence of infections. All of these factors are key indicators that you might have a microbial imbalance.
If you believe you might have low levels of Lactobacilli spp, consider a Thryve Vaginal Health Test in 2021. This vaginal microbiome assessment gives you everything you need to safely procure a vaginal sample from your own home.
All vaginal samples are analyzed with 16s rRNA gene sequence technology. We then breakdown the analysis of the microbiome into insights you can follow to make improvements in your overall wellness routine.
We follow the general vaginal community state types (CSTs) as recommended by many leading gynecologists and specialists of the vaginal microbiome. We use your insights to give you a CST classification. That way, you and your doctor can make educated decisions about your health.
What are the 5 general vaginal community state types?
One of the most pivotal elements of the Thryve Vaginal Health Program is learning which of the vaginal community states types (CSTs) represent your current microbial network. These insights can provide information about reproductive health, vaginal comfort, and other immune factors. Here is a breakdown of each vaginal community state type.
Vaginal Community State Type I (CST I)
Of the vaginal community state types, CST I is deemed the healthiest. It is heavily dominated by Lactobacillus Crispatus. L. Crispatus doesn’t play well with others. When there is a relative abundance of this Lactobacilli, it comprises 80% to 90% of the entire vaginal bacterial community composition.
L. Crispatus produces an abundance of lactic acid. Therefore, it drastically prohibits the spread of pathogenic bacteria, such as Prevotella and Gardnerella Vaginalis . Also, those with an abundance of L. Crispatus have a stronger immune response to sexually transmitted infections (STIs), including chlamydia .
Those with this CST classification tend to be women of childbearing age. Those who have a CST I classification during pregnancy have an increased chance of full-term delivery. Bifidobacteria may also be found within healthy vaginal biomes. Bifidobacterium contributes to the development of a baby’s immune system .
Confirming you have a CST I classification with a Thryve Vaginal Health Kit is an excellent first step in the conception process. That way, you can rule out potential hurdles that might create an increased risk of preterm delivery.
Health effects of Vaginal Community State Type I (CST I)
• Overall vaginal health
• Most protective: highest lactic acid production & bacteriocins production
• Reproductive health
• Lower risk of urinary tract infections (UTIs), bacterial vaginosis, and sexually transmitted infections (STIs)
Vaginal Community State Type II (CST II)
A CST II categorization means you have a healthy vaginal microbiome. However, this vagina is not acidic as a CST I. That’s because the dominant Lactobacillus spp in CST II is Lactobacillus Gasseri.
Lactobacillus Gasseri might not produce as much lactic acid as Lactobacillus Crispatus, but they still show clinical significance in promoting a healthy vagina . People with a CST II classification have a decreased risk of developing bacterial vaginosis, UTIs, and STIs.
As women enter perimenopause, their vaginal bacteria community composition changes. This alteration is due to less estrogen in the body. When these needs change, Lactobacillus Gasseri steps up to ensure a healthy environment. That’s why many perimenopausal women have a CST II classification.
Health effects of Vaginal Community State Type II (CST II)
• Vaginal health, relatively stable microbiome
• Lower risk of urinary tract infections (UTIs), bacterial vaginosis, sexually transmitted infections (STIs)
Vaginal Community State Type III (CST III)
A vaginal community state type of CST III is still considered healthy. It is dominated by Lactobacillus iners. While we’re fans of vaginal Lactobacilli, a CST III categorization is not as optimal as CST I. It’s like a yellow traffic light warning you that a hard stop might need to come soon.
A CST III classification may indicate an unstable vaginal microbiome. It’s often associated with vaginal dysbiosis, also known as leaky vagina.
Those with a CST III classification may have:
• A microbial imbalance that’s not D-lactate Lactobacilli dominant
• High microbial diversity
• Inflammation and other immune responses
The goal of a healthy human vagina is to have as little bacterial diversity as possible. When other microorganisms take up residence, you become more prone to opportunistic pathogens entering the system.
A person with a CST III classification is at an increased risk of human papillomavirus (HPV), cervical dysplasia, and UTIs.
Health effects of Vaginal Community State Type III (CST III)
• Decreased protection against pathogenic growth
• Higher risk of vaginal dysbiosis, bacteria vaginosis, HPV infections, cervical dysplasia, and urinary tract infections (UTIs)
Vaginal Community State Type IV (CST IV-A and CST IV-B)
A CST classification of IV may indicate a bacterial imbalance in the vaginal microbiome. That generally indicates you have a high diversity of microbial species in the region. Even worse, the levels of Lactobacillus species are low.
Being classified as CST IV suggests you may be at risk for the growth of harmful bacteria. Those with a CST IV classification may need to inoculate the vaginal microbiome with supplemental Lactobacilli.
Women most susceptible to a CST IV classification are postmenopausal. When estrogen levels taper off, it causes the presence of Lactobacilli to deplete. In turn, the vaginal microbiome has less lactic acid protection. This drop-in probiotic bacteria creates an open field susceptible to pathogenic overgrowth.
There are thousands of known bacteria in the microbiome. These microorganisms are all fighting for survival. For specific bacteria to survive, they must find other bacteria in which they coexist. Groups of bacteria that hang out together are known as commensal bacteria.
When it comes to vaginal health, you don’t want diversity. For opportunistic pathogens, it’s about strength in numbers when various species are vying to compete against a spectrum of vaginal Lactobacilli.
There seem to be specific recipes of commensal bacteria that can help create an environment that decreases Lactobacillus levels. This split in cohabitators is broken down into two types of CST IV classifications.
The two types of CST IV include:
• CST IV-A – High levels of Anaerococcus, Peptoniphilus, Prevotella, and Streptococcus
• CST IV-B – High levels of Atopobium vaginae, Megasphaera, and others
It is not uncommon for both classifications to have elevated levels of Gardnerella Vaginalis. This opportunistic pathogen is extremely dangerous to women’s health. Gardnerella Vaginalis creates a biofilm that promotes antibiotic resistance. It also can lead to recurrent vaginal infections .
Those with a CST IV classification are at an increased risk of human immunodeficiency virus infection (HIV) transmission. They might also encounter pregnancy issues, including preterm delivery.
Health effects of CST IV
• Bacterial vaginosis
• Not protective
• High diversity, not considered a healthy vaginal microbiome
• Symptoms associated include burning, itching, urgency to urinate, and discharge
• Recurrent urinary tract infections (UTIs)
• Higher risk of HIV
• Gynecological and vaginal infections and disorders
Vaginal Community State Type V (CST V)
Last is certainly not the least here. It’s just rare. A vaginal community state type V (CST V) is dominated by Lactobacillus Jensenii. Lactobacillus Jensenii produces an adequate amount of lactic acid . So, it’s hard for pathogenic bacteria to penetrate the system in its presence.
Those with a CST classification V tend to be peri and post-menopausal women. They will have a lower risk of developing bacterial vaginosis, STIs, or recurrent UTIs.
Health effects of CST V
• Vaginal health
• Lower risk of UTIs
Determining vaginal community state types
Knowing your vaginal community state type can help you make invaluable decisions about your reproductive (and overall) health. One of the most efficient ways to learn more about your own vaginal microbiome is with a Thryve Vaginal Health Test Kit in 2021.
We use DNA testing to determine your vaginal CST. With that information, we provide you with actionable suggestions, such as food and probiotic recommendations. Please use this test, along with a yearly examination, to make conscious health decisions with your healthcare provider.
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