The STI Files: Bacterial Vaginosis

Stat: Bacterial vaginosis⁠ (BV) is the most common cause of vaginitis⁠ symptoms among people of childbearing age (15-45). However, half the people who meet clinical criteria for BV have no symptoms.

What is it exactly? Bacterial vaginosis is an infection⁠ that only occurs to people who have a vagina⁠ . BV reflects a change in the vaginal bacterial environment. A healthy vagina contains several different kinds of bacteria in balance with each other so that no one type outnumbers all the others. BV results when an imbalance, including pH changes, occurs in the vagina because the amount of one or two types of bacteria has increased and outnumbered the rest. There's no one type of bacteria which are always responsible: any number of different bacteria can cause BV.

The root cause of this disruption in the balance of the vaginal flora is not fully understood. Douching can increase the risk of acquiring BV. It isn't exactly clear what role sexual⁠ activity may have as BV can occur in people with vaginas who are not sexually active⁠ . However, people who are sexually active do run a high risk of developing the condition, as do those with multiple partners or who have changed partners recently. BV is also one of the more common infections among lesbian⁠ cisgender⁠ women.

About how many people have it? Statistics are elusive, but it's estimated that over 2 million people in America have BV at any given time.

How is it spread? BV can result any time something causes a change in the vaginal environment, making it easier for an overgrowth of one particular bacteria to occur, or from activities which introduce new bacteria into the vagina. This can be achieved through vaginal or anal intercourse⁠ , manual sex⁠ , shared sex⁠ toys, vaginal intercourse⁠ wearing a condom⁠ that was also used for anal intercourse or through nonsexual activities such as wiping improperly after a bowel movement or the use of antibiotics. BV is often more common for people with new sexual partners than for those who have been in the same partnership(s) for a while.

What are its symptoms? The main symptom of BV is often a thin, creamy greyish-white, odorous vaginal discharge⁠ . A sudden increase in discharge that does not seem to pass within a handful of days or which isn't related to the appropriate fertility⁠ phase can often be a sign of BV. A fishy-like odor is sometimes noticeable, especially after intercourse⁠ or exercise. Some people with BV may have mild itching or burning with urination. Nearly half of the people with clinical signs of BV, however, report no symptoms.

How is it diagnosed? By an examination of a sample of vaginal fluid under a microscope, either stained or in special lighting, to detect the presence of the organisms associated with BV. Diagnosis is based on the absence of lactobacilli, the presence of numerous "clue cells" (cells from the vaginal lining that are coated with BV organisms), a fishy odour, and/or decreased acidity or change in pH of vaginal fluid.

Is it treatable? Yes. People can be treated with antibiotics such as metronidazole or clindamycin. Generally, sex partners who have penises are not treated.

Is it curable? Yes, but you can contract it again.

Can it affect fertility? BV is associated with premature delivery, low birth weight, and pelvic inflammatory disease, and may increase the risk of contracting STIs such as chlamydia⁠ and gonorrhea⁠ which can also impact fertility .

Can it cause death? Not by itself, no. But bacterial vaginosis⁠ can increase the risk for HIV⁠ infection for which there is no cure and which can lead to AIDS⁠ and other fatal illnesses. Pregnant people with BV run higher risks of miscarriage⁠ , especially in the first trimester.

How can we protect against it? Do not do, avoid or limit the following activities which can lead to the introduction of the bacteria to the vagina or change the vaginal environment:

  • douching
  • unprotected vaginal or anal intercourse
  • unprotected manual sex
  • vaginal intercourse wearing a condom that was also used for anal intercourse - read how to use a condom)
  • poor toileting hygiene (wipe from front to back after urinating or bowel movements, not back to front)
  • sharing sex toys, particularly those that cannot be boiled before use or which have not been or cannot be covered with a condom.

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