Bacterial Vaginosis - What is it?

Bacterial Vaginosis - What is it?

What is bacterial vaginosis (BV)? 

Bacterial vaginosis, or BACTERIAL VAGINOSIS, is the diagnosis given when you have a high diversity of bacteria in your vaginal microbiome — including an overgrowth of some bacteria like Gardnerella that may be harmful. (Need a refresher on the vaginal microbiome? We've got you)
This overgrowth in vaginal flora is in contrast to a healthy vaginal microbiome, which is dominated by Lactobacilli, a lactic-acid producing bacteria that resist pathogens. When the lactobacilli-dominance is disrupted, your vaginal pH can go up, allowing other types of bacteria to grow and cause an imbalance (sometimes referred to as dysbiosis) — which then causes a variety of symptoms.
BACTERIAL VAGINOSIS is typically diagnosed two ways. The first is symptomatically, based on something called the Amsel criteria. An Amsel criteria diagnosis is when you have 3 of the 4 following symptoms: white discharge, clue cells, a pH over 4.5, and a fishy odor.
The more specific way to diagnose BACTERIAL VAGINOSIS is with a Nugent score. Using the Nugent score, a vaginal smear is examined under a microscope for three bacteria morphotypes: Lactobacillus, Gardnerella, and curved gram rods. A score is then created based on how many of each type have been counted, essentially looking for low, intermediate, or high diversity of bacteria in the sample. A score under 4 is diagnosed as healthy, 4-7 is intermediate, and 7-10 is considered high diversity, aka, BACTERIAL VAGINOSIS.
You may have noticed that “high diversity” isn’t a very specific diagnosis — and you’re right. Unfortunately, current diagnostic measures don’t tell you much about what other bacteria are present or any other relevant information about how they’re interacting in your vaginal microbiome.
(A small aside — this is why we’re creating an at-home vaginal microbiome test, so you can understand all the bacteria present in your microbiome and why it matters, including what symptoms it may be related to. Though it’s not a diagnostic test, and shouldn’t replace the advice of your doctor, it can help you uncover what strains are present and in what capacity.)
Bacteria that is adhered to vaginal epithelial cells, known as clue cells. The presence of these clue cells is one of the signs that the patient has bacterial vaginosis. CDC/ M. Rein
What are the symptoms of bacterial vaginosis?
The most common complaints of folks with BACTERIAL VAGINOSIS are:
  • A fishy odor
  • White or gray vaginal discharge

Pain, discomfort, or itchiness, both in general or specifically with sex or peeing, may also occur. However, up to 84% of people with BACTERIAL VAGINOSIS (read: an imbalanced vaginal microbiome) may not experience anything at all. 


If you’re dealing with BACTERIAL VAGINOSIS, you’re far from alone. According to the Center for Disease Control (CDC), BACTERIAL VAGINOSIS is actually the most common vaginal condition in women ages 15-44. In fact, almost 30% of people with vaginas get BACTERIAL VAGINOSIS each year, and that number jumps to 50% for people of reproductive age (those in between puberty and menopause).


Here’s a frustrating tidbit from the CDC: “Researchers do not know the cause of
BACTERIAL VAGINOSIS or how some women get it.” 
If you’re shocked that this is the best available answer for a condition that affects one in three women, you’re not alone. This is why Evvy exists! The vaginal microbiome and BACTERIAL VAGINOSIS are massively understudied, and it’s time women and people with vaginas got the research and care they deserve.

Can you get BACTERIAL VAGINOSIS from having sex?

BACTERIAL VAGINOSIS is not a sexually-transmitted infection (STI) and you can develop BACTERIAL VAGINOSIS without ever having sex. 

Because BACTERIAL VAGINOSIS is broadly defined as an imbalance in your vaginal microbiome, you can’t “get” BACTERIAL VAGINOSIS from having sex with someone. That said, sex itself (or really putting anything in or near your vagina) can introduce new bacteria and/or change the vaginal pH, allowing “bad” bacteria an opportunity to overgrow and cause BACTERIAL VAGINOSIS.  

Semen, saliva, or another vaginal microbiome can all disrupt your vaginal flora. This means that having unprotected sex, sex with a new partner, or sex with someone else with a vagina can increase your odds of developing BACTERIAL VAGINOSIS — but read on to discover a few steps you can take to help prevent BACTERIAL VAGINOSIS.

How can I stop BACTERIAL VAGINOSIS from coming back again?

One way to help prevent a BACTERIAL VAGINOSIS recurrence is to take a probiotic with helpful strains of vaginal bacteria regularly. This ensures that protective bacteria is always being introduced to strengthen your natural defense against pathogens — even if you’re taking antibiotics or using boric acid.

There are other every day behaviors you can do to help, and you’ve probably heard of some of them:

Avoid douching and feminine hygiene products, which can imbalance your
  • Wipe front to back
  • Change your period products within the proper time frame
  • Stick to underwear that is loose fitting, lightweight, breathable, and made from a natural fabric, and change it often
  • Wash sex toys often 
  • Reconsider smoking and diet habits (smoking and unhealthy fats are linked to an increased risk of BACTERIAL VAGINOSIS) 
  • Incorporate meditation, yoga or exercise into your daily routine (the stress hormone cortisol can disrupt your vaginal flora!)

What are the risks associated with BACTERIAL VAGINOSIS?

The bacteria present in the vagina influence the risk of a variety of other health issues. Untreated BACTERIAL VAGINOSIS is associated with the following conditions, among others:

  • STIs: chlamydia, gonorrhea, trich, herpes, HPV, HIV 
  • Pelvic Inflammatory Disease
  • Fertility issues: infertility, failed IVF
  • Pregnancy issues: miscarriage, preterm birth, neonatal problems preeclampsia
  • Gynecological cancers: Ovarian, Cervical
  • Cervicitis
  • Toxic Shock Syndrome

What’s the difference between BACTERIAL VAGINOSIS and a yeast infection?

BACTERIAL VAGINOSIS is not the same thing as having a yeast infection (also known as thrush), which is caused by candida (yeast). The main underlying difference is that yeast infections are caused by an overgrowth of candida, while BACTERIAL VAGINOSIS is caused by an overgrowth of a variety of bacteria like gardnerella.  Though the symptoms in these two vaginal infections may overlap, yeast infections are typically characterized by a specific type of vaginal discharge (often compared to cottage cheese) and itchiness, while BACTERIAL VAGINOSIS is mostly associated with a fishy odor and thin white or grey discharge.

Are hormones related to BACTERIAL VAGINOSIS?

Hormones play a role in the composition of  the vaginal microbiome. Estrogen is an important variable in the health of your lactobacilli, the bacteria that create a lactic acid dominant environment in the vagina. Anything that changes estrogen levels can introduce risk of imbalancing the vaginal microbiome. This means that there are times when it’s important to pay extra attention to your vaginal microbiome: starting your period, becoming pregnant, going through menopause, and going on or changing hormonal birth control.


Only people with vaginas can develop BACTERIAL VAGINOSIS, because by definition it is an imbalance in the vaginal microbiome. The penis has its own microbiome — but we’ll leave that for another day! 

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