Bacterial vaginosis (BV) happens when the protective bacteria in the vagina lose ground to other microbes that normally exist in small numbers. It’s the most common vaginal infection in women of reproductive age, and between 50% and 80% of women who treat it successfully will experience a recurrence within 6 to 12 months. That high recurrence rate makes prevention just as important as treatment.
The good news: most of the factors that trigger BV are things you can control. Here’s what actually works.
What Causes the Imbalance
A healthy vagina is dominated by Lactobacillus bacteria, which keep the environment acidic (low pH) and crowd out harmful organisms. BV develops when Lactobacillus populations drop and anaerobic bacteria from groups like Gardnerella, Prevotella, and Mobiluncus multiply in their place. For a long time, researchers believed Lactobacillus protected you mainly by producing hydrogen peroxide. More recent evidence suggests the real defense comes from maintaining an acidic pH and other factors that aren’t fully understood yet.
The practical takeaway: anything that disrupts your vaginal pH or kills off Lactobacillus raises your risk. Prevention is really about protecting that bacterial community.
Stop Douching
Douching is the single most well-documented habit that increases BV risk, and it’s also the easiest to stop. Women who douche at least once a month have a 1.4 times higher risk of developing BV or an intermediate disruption in vaginal flora. That risk jumps to 2.1 times higher in women who douched within the past week. Douching strips away the Lactobacillus that maintain a protective environment, creating space for the anaerobic bacteria behind BV to take over.
The vagina is self-cleaning. Warm water on the external vulva during a shower is all you need. Internal rinsing with any fluid, whether it’s water, vinegar, or a commercial douche product, works against you.
Skip Scented Products Near Your Vagina
Scented tampons, pads, wipes, and herbal-infused menstrual products can upset the bacterial balance in the vagina. They give harmful bacteria the upper hand by disrupting Lactobacillus populations, which can lead to irritation, itching, and infections including BV. The same goes for scented soaps, body washes, and bubble baths used in or around the vaginal area.
Stick to unscented menstrual products and, if you use soap on the vulva at all, choose something fragrance-free and gentle. During your period, change tampons and pads regularly rather than leaving them in for extended periods.
Use Condoms Consistently
Sexual activity is one of the strongest risk factors for BV. The CDC lists multiple sex partners, a new sex partner, and lack of condom use as associated factors. Condoms create a barrier that prevents direct exposure to bacteria from a partner and limits pH disruption during intercourse.
This applies whether your partner is male or female. BV is associated with both male and female sexual partners. If you’re being treated for BV, using condoms during the entire treatment period is especially important to give your vaginal flora time to recover.
Quit Smoking
Smoking has a surprisingly strong connection to BV. Research published in BMJ’s Sexually Transmitted Infections journal found that smokers were seven times more likely to have a vaginal bacterial community dominated by anaerobes (the type linked to BV) rather than the protective Lactobacillus crispatus. The more a person smoked, as measured by cotinine levels and carbon monoxide, the more disrupted their vaginal microbiome was.
The exact mechanism isn’t fully mapped out, but smokers consistently have lower proportions of Lactobacillus in their vaginal flora. If you’re dealing with recurrent BV, quitting smoking may be one of the more impactful changes you can make.
Choose Breathable Underwear
Excess moisture in the vaginal area creates conditions where bacteria and yeast thrive. Cotton underwear is the best choice because it’s breathable and wicks away sweat. Synthetic fabrics trap heat and moisture against the skin. Even underwear marketed as having a “cotton crotch panel” doesn’t fully protect you from the surrounding synthetic material and won’t breathe the way 100% cotton does.
A few other clothing habits that help:
- Change underwear daily to prevent bacterial buildup and exposure to fecal matter.
- Go underwear-free at night or wear loose pajamas or boxer shorts, which increases airflow and can help if you’re prone to vaginal infections.
- Skip panty liners for daily discharge. They reduce breathability and can cause irritation. Normal vaginal discharge doesn’t require a liner.
- Avoid tight, non-breathable clothing for extended periods, especially during workouts. Change out of sweaty clothes promptly.
The Truth About Probiotics
Probiotic supplements marketed for vaginal health are popular, but the evidence for preventing BV is mixed at best. A controlled study testing two of the most commonly recommended strains (Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14) as an add-on to standard antibiotic treatment found no improvement in cure rates. At 30 days, the cure rate was about 58% with probiotics and 60% without. By 90 days, the probiotic group actually had a slightly lower cure rate (37% vs. 49%), though the difference wasn’t statistically significant.
This doesn’t mean probiotics are harmful, but they shouldn’t be your primary prevention strategy. If you want to try them, they’re unlikely to cause problems. Just don’t rely on them in place of the lifestyle changes that have stronger evidence behind them.
Wiping and Bathroom Habits
Always wipe front to back after using the toilet. Fecal bacteria that migrate toward the vaginal opening can disrupt the microbial balance. This is a simple habit, but it matters, especially since daily exposure adds up over time.
After swimming or exercising, change out of wet or damp clothing as soon as practical. Prolonged moisture against the vulva creates the warm, damp environment that anaerobic bacteria prefer.
Why BV Keeps Coming Back
Even with good prevention habits, BV has a frustratingly high recurrence rate. Between 50% and 80% of women who complete antibiotic treatment will have another episode within 6 to 12 months. Researchers believe this happens partly because the anaerobic bacteria form protective structures called biofilms on the vaginal wall that antibiotics can’t fully eliminate, allowing them to regrow once treatment stops.
If you’re in this cycle, it’s worth reviewing all the factors above systematically. Often, recurrent BV isn’t caused by one thing but by a combination: a new partner plus scented products, or smoking plus inconsistent condom use. Addressing multiple factors at once gives your Lactobacillus the best chance of re-establishing dominance and keeping the vaginal environment stable long-term.