Preventing bacterial vaginosis (BV) comes down to protecting the natural balance of bacteria in your vagina, specifically the protective bacteria that keep your vaginal pH acidic and inhospitable to harmful microbes. While no strategy guarantees you’ll never get BV, several evidence-backed habits significantly lower your risk.
What Actually Causes BV
Your vagina naturally hosts a community of bacteria dominated by Lactobacillus species. These bacteria produce lactic acid, which maintains a vaginal pH between 3.5 and 4.5. That acidic environment keeps harmful anaerobic bacteria in check. BV develops when something disrupts this balance, causing Lactobacillus populations to drop sharply while anaerobic bacteria multiply and take over.
The result is an elevated, more alkaline pH that allows organisms like Gardnerella vaginalis and other anaerobes to flourish. This is what produces the characteristic thin discharge and fishy odor associated with BV. Understanding this mechanism matters because nearly every prevention strategy targets the same goal: keeping Lactobacillus dominant and your vaginal pH low.
Stop Douching
Douching is one of the strongest modifiable risk factors for BV. The CDC lists it alongside multiple sexual partners and lack of condom use as a primary driver of vaginal bacterial imbalance. When you flush water or a cleansing solution into the vaginal canal, you physically wash away the Lactobacillus colonies that maintain your acidic environment. This creates an opening for anaerobic bacteria to establish themselves.
Your vagina is self-cleaning. The discharge you produce is part of that process. Cleaning the external vulva with warm water (or a mild, unscented soap on the outer skin only) is all you need. Scented washes, sprays, and wipes marketed for vaginal freshness can cause the same kind of disruption as douching, so it’s worth avoiding those too.
Use Condoms Consistently
Lack of condom use is a recognized risk factor for BV. Semen is alkaline, with a pH around 7.2 to 8.0, which temporarily raises vaginal pH after unprotected sex. For most people this shift is brief, but repeated exposure can create conditions that favor anaerobic bacterial growth over Lactobacillus.
Having a new sexual partner or multiple partners also increases BV risk independently, likely because new partners introduce unfamiliar bacteria into the vaginal environment. Condoms create a barrier that limits both semen exposure and bacterial exchange. If you’re in a long-term monogamous relationship and not experiencing recurrent BV, this factor may matter less for you. But if BV keeps coming back, consistent condom use is one of the more effective changes you can make.
One important note: BV-associated bacteria can be found on male genitalia, but treating a male partner with antibiotics has not been shown to prevent BV recurrence in women. This isn’t something your partner can fix on their end.
Choose Breathable Underwear
Moisture-trapping clothing creates a warm, damp environment where bacteria and yeast thrive more easily. Cleveland Clinic dermatologists recommend 100% cotton underwear because cotton wicks away excess sweat and moisture far better than synthetic fabrics. If your underwear has a synthetic outer layer with just a cotton crotch panel, that small panel doesn’t fully protect you from reduced breathability.
Looser-fitting bottoms help too, especially if you’re prone to recurrent vaginal infections. Tight leggings or skinny jeans worn for long stretches trap heat and moisture against the vulva. You don’t need to overhaul your wardrobe, but switching to cotton underwear and changing out of sweaty workout clothes promptly makes a real difference over time.
Panty liners are another common culprit. While many people wear them daily to absorb normal discharge, they actually decrease breathability and can cause irritation. Unless you need them for incontinence or your period, skipping daily panty liners is better for your vaginal environment.
Be Careful With Products Near Your Vagina
Anything that contacts the vaginal area can potentially shift your bacterial balance. Scented tampons, pads, bubble baths, bath bombs, and laundry detergents with heavy fragrances all introduce chemicals that can irritate vaginal tissue and disrupt your microbiome. Switching to unscented versions of these products removes a common source of low-grade irritation that you might not even notice until infections stop recurring.
The same applies to lubricants during sex. Oil-based and glycerin-containing lubricants can alter vaginal pH or promote bacterial growth. Water-based, pH-balanced lubricants are the safest choice for maintaining your vaginal environment.
Probiotics for BV Prevention
Because BV is fundamentally a loss of Lactobacillus, researchers have studied whether replacing those bacteria directly could help prevent it. The most promising strain is Lactobacillus crispatus, which has been tested in clinical trials as a vaginal suppository at doses ranging from 500 million to 2 billion colony-forming units (CFUs). These trials have focused on using probiotics after antibiotic treatment to help recolonize the vagina with protective bacteria and prevent relapse.
Over-the-counter oral probiotics marketed for vaginal health are widely available, but the evidence for oral probiotics preventing BV is weaker than for vaginally applied formulations. If you want to try probiotics, look for products containing Lactobacillus crispatus or Lactobacillus rhamnosus, the two strains with the most research behind them. They’re unlikely to cause harm, but they shouldn’t be your only prevention strategy.
Managing Recurrent BV
About half of people treated for BV experience a recurrence within 12 months, which makes prevention particularly frustrating for those stuck in a cycle. If BV keeps coming back, the lifestyle changes above become even more important, but you may also need additional medical support.
Boric acid vaginal suppositories have gained popularity for recurrent BV. One study of 105 women with recurrent infections found that boric acid used alongside antibiotic therapy produced a 69% cure rate at six months. A separate randomized trial of a boric acid-based formulation showed 50 to 59% efficacy for early clinical cure. These are encouraging numbers, but research on boric acid alone (without antibiotics) for recurrent BV is still limited. Boric acid is toxic if swallowed, so these suppositories are strictly for vaginal use.
Extended or suppressive courses of prescription medication after an initial treatment round can also help break the cycle. If you’ve had three or more episodes in a year, this is worth discussing with a healthcare provider, since the standard single course of treatment clearly isn’t enough on its own for your situation.
Habits That Support Vaginal Health Overall
A few broader habits support the conditions Lactobacillus needs to thrive. Smoking is an independent risk factor for BV, likely because it reduces immune function in vaginal tissue. Quitting or reducing smoking lowers your risk. Stress and poor sleep also suppress immune function in ways that may make your vaginal microbiome less resilient, though these links are harder to quantify.
After using the bathroom, always wipe front to back to avoid introducing rectal bacteria into the vaginal area. Change out of wet swimsuits promptly. During your period, change tampons and pads regularly, since menstrual blood is slightly alkaline and can raise vaginal pH. These are small habits, but BV prevention is really about the cumulative effect of reducing repeated disruptions to your vaginal ecosystem rather than any single dramatic intervention.