Untreated BV: Complications & Long-Term Risks

Untreated BV (bacterial vaginosis) often clears on its own, but leaving it untreated raises real risks: it makes acquiring HIV and other STIs more likely, can spread to the upper reproductive tract, and tends to recur. BV is the most common vaginal condition in women ages 15–44 and is easy to treat once diagnosed.

The essentials: what BV is and why untreated cases matter

BV isn't an infection you catch from a single germ. It's an imbalance. The vagina normally runs on protective Lactobacillus bacteria, which keep the environment acidic and crowd out troublemakers. In BV, those lactobacilli are replaced by an overgrowth of anaerobic bacteria, and that shift produces both the symptoms and the risks CDC, About BV.

BV isn't classified as a traditional sexually transmitted infection, but it's clearly linked to sexual activity, and women who've never been sexually active are rarely affected. We cover that nuance in depth in is bv an std or not? what science says.

Untreated BV deserves its own page because of the downstream risk. When protective lactobacilli disappear, the vaginal lining loses some of its natural defense. A meta-analysis of more than 30,000 women found BV raised the risk of acquiring HIV by about 60% (RR 1.61) Atashili et al., AIDS. BV is also associated with easier acquisition of other STIs and, in some cases, with pelvic inflammatory disease (PID), an infection that ascends from the vagina and cervix into the uterus and fallopian tubes, where it can cause scarring that threatens fertility. None of this is a reason to panic, but it is a reason to treat BV rather than wait it out indefinitely.

Symptoms of BV (and why 'no symptoms' doesn't mean no risk)

The classic signs are a thin white or gray discharge and a strong fish-like odor that's often most noticeable after sex. Some people also notice itching, burning, or burning when they urinate. The odor comes from amines released by the anaerobic bacteria, the same chemistry behind the "whiff test" clinicians use to diagnose it.

Many people with BV have no symptoms at all. A silent case still carries the altered vaginal environment that raises STI and HIV risk, which is one reason testing matters even when nothing feels wrong. If your only complaint is odor that keeps coming back, that's worth a visit rather than another round of over-the-counter products that don't treat BV.

How BV is diagnosed

Clinicians have three main routes to a diagnosis. The Amsel criteria require at least three of the following: thin discharge, clue cells (vaginal cells coated with bacteria, seen under the microscope), a vaginal pH above 4.5, and a positive whiff or fishy-odor test. The Nugent score, read from a Gram-stained slide, is the laboratory reference standard. There are also FDA-cleared molecular tests that detect the bacterial DNA patterns of BV.

Testing is simple. Most cases are diagnosed from a quick exam or a self-collected swab, with results usually back within a few days, and care is free or low-cost at health departments, Planned Parenthood, and Title X clinics. Because untreated BV travels with other infections that share symptoms, it's reasonable to get tested for STIs at the same visit. If a specific exposure is on your mind, timing matters, so see when to test after exposure so you don't test too early to catch something.

Treatment: what cures BV and what untreated cases need

BV responds well to antibiotics. The CDC-recommended regimens are metronidazole 500 mg orally twice daily for 7 days; metronidazole 0.75% gel, one 5 g applicator intravaginally daily for 5 days; or clindamycin 2% cream intravaginally at bedtime for 7 days CDC STI Tx Guidelines, 2021. Your clinician will help you choose based on your preferences and history. For the full picture, see our guide to bv treatment.

A few practical points the 2021 guidelines settled. You no longer need to avoid alcohol while taking metronidazole; there's no convincing evidence of a reaction. Routine treatment of male partners is not recommended. Clindamycin cream and ovules are oil-based, so they can weaken latex condoms during and shortly after use.

Finish the whole course even after the odor and discharge fade. Stopping early is a common reason BV comes back. Standard antibiotics cure roughly 80 to 90% of acute episodes, but BV recurs in up to 60% of women within 12 months SASGOG. Recurrent BV, defined as three or more episodes a year, is usually managed with a months-long maintenance regimen rather than just another single course. If your BV keeps coming back, say so, because the plan changes.

How to prevent BV and its complications

You can't make the vaginal microbiome behave on command, but a few habits lower the odds of BV and its return. Don't douche; it strips out protective bacteria and worsens the imbalance. Use condoms correctly every time, which is linked to lower BV risk and protects against the STIs that ride along with it. Limiting the number of partners also reduces risk.

• Skip douching and harsh internal washes, since they disrupt the lactobacilli that protect you.
• Use condoms consistently; they lower risk for BV and for the STIs untreated BV makes easier to catch.
• Test routinely, since BV and many STIs can be completely silent.
• Treat recurrences as a pattern. Recurrent BV needs a different, longer plan.

For a fuller walkthrough, see our guide on how to prevent bv. Routine testing is part of prevention too, since it catches what has no symptoms before it can raise your risk.

When to see a clinician

See a clinician if you have a new or persistent discharge or odor, if symptoms return after treatment, if you have three or more episodes in a year, or if you're pregnant and notice symptoms. Also get evaluated if you have pelvic pain, fever, or pain during sex; those point beyond simple BV toward an ascending infection like PID that needs prompt care. A BV diagnosis is common, treatable, and handled daily in clinics; it says nothing about you as a person.