Bacterial vaginosis happens when the naturally acidic environment of the vagina shifts, allowing organisms that thrive in less acidic conditions to multiply and crowd out the protective bacteria that normally keep things in balance. Up to 69% of women who are treated for BV will have it come back within 12 months, which makes prevention just as important as treatment. The good news is that several everyday habits directly influence whether your vaginal environment stays stable or tips toward infection.
What Keeps the Vagina Healthy
A healthy vagina maintains a pH between 4.0 and 4.5, which is moderately acidic. That acidity comes from lactic acid produced by beneficial bacteria that dominate the vaginal environment. These bacteria don’t just occupy space. They actively produce compounds that kill or suppress the organisms responsible for BV. When pH rises above 4.5, those protective bacteria lose their advantage, and BV-associated species begin to take over, producing fishy-smelling compounds called biogenic amines.
Anything that raises vaginal pH or reduces the population of protective bacteria can trigger this shift. Some of these triggers are avoidable, others are manageable, and understanding them gives you real control over your risk.
Stop Douching
Douching is one of the most well-documented risk factors for BV. The vagina is self-cleaning. Introducing water, vinegar, or commercial douching products directly into the vaginal canal washes away the protective bacteria and disrupts the acidic environment they maintain. The CDC lists douching as a primary behavior that upsets the normal balance of vaginal bacteria. There is no medical benefit to douching, and the practice consistently increases infection risk.
If you’re douching because of odor or discharge, those symptoms may already indicate an imbalance that douching will only worsen. Cleaning the external vulva with warm water is sufficient for hygiene. Mild, unscented soap on the outer skin is fine, but nothing needs to go inside the vaginal canal.
Use Condoms Consistently
Semen has an alkaline pH, which is the opposite of what the vagina needs. When semen enters the vaginal canal, it temporarily raises the pH, creating conditions where protective bacteria struggle and BV-associated species can gain a foothold. Research published in 2021 found that recent semen exposure alters the immune environment of the vaginal lining and shifts the bacterial balance toward organisms linked to BV.
Consistent condom use prevents this pH disruption entirely. BV is also associated with new sexual partners and multiple partners, likely because each person introduces a different microbial community. Condoms act as a barrier against both the alkaline effect of semen and the introduction of unfamiliar bacteria. The CDC recommends condom use during BV treatment specifically because unprotected sex can undermine recovery, but the same logic applies to prevention.
Choose the Right Lubricant
Not all lubricants are created equal, and some popular products can damage vaginal tissue and disrupt the bacterial balance. The key factor is osmolality, which measures how concentrated a solution is. The World Health Organization recommends vaginal lubricants stay under 1,200 mOsm/kg with a pH around 4.5. Products that exceed this threshold pull water out of vaginal cells, causing damage to the tissue lining and making infection more likely.
To put this in perspective, here’s how some common products measure up:
- Good Clean Love Almost Naked: 270 mOsm/kg, well within the safe range, made with aloe and lactic acid
- K-Y Jelly: 2,500 mOsm/kg, more than double the WHO limit
- Astroglide Liquid: 6,100 mOsm/kg, five times the recommended maximum, and contains a formaldehyde-releasing preservative
- K-Y Warming Jelly: 13,000 mOsm/kg, more than ten times the safe threshold
Glycerin and propylene glycol are the main ingredients that drive osmolality up. When shopping for lubricant, look for water-based products with low osmolality, no glycerin, and an acidic pH. Avoid anything containing nonoxynol-9 (a spermicide), which disrupts the vaginal cell barrier.
Wear Breathable Underwear
Moisture creates a welcoming environment for the bacteria and yeast you don’t want. Cotton is the best fabric for underwear because it wicks away sweat and allows airflow. Synthetic materials like nylon and polyester trap heat and moisture against the skin, which encourages microbial overgrowth.
A cotton crotch panel sewn into synthetic underwear isn’t a reliable substitute. That small patch doesn’t provide the same breathability as a fully cotton garment, and the surrounding synthetic fabric still traps moisture. If you deal with recurrent vaginal infections, Cleveland Clinic physicians recommend switching to 100% cotton and choosing looser fits. Panty liners also reduce breathability and can cause irritation when worn daily, so reserve them for when you actually need them.
Quit Smoking
Smoking affects the vagina in ways most people don’t expect. Nicotine and its breakdown products accumulate in vaginal tissue, and research has found that smoking is associated with measurable changes in vaginal chemistry. Among women who already have a less protective bacterial profile, smokers show substantially higher levels of biogenic amines, the same compounds that cause the characteristic fishy odor of BV and that help harmful bacteria resist the acidic environment.
Smoking also appears to reduce lactic acid concentrations in the vagina. Since lactic acid is the primary weapon protective bacteria use against BV-associated organisms, lower levels mean weaker defenses. Quitting smoking won’t transform your vaginal microbiome overnight, but it removes a chemical stressor that actively undermines the environment your body is trying to maintain.
Consider Probiotics
Oral probiotics containing specific bacterial strains can help restore and maintain a healthy vaginal environment, particularly after treatment for BV. A randomized, double-blind trial found that women who took oral probiotics alongside standard antibiotic treatment had an 88% cure rate at 30 days, compared to just 40% for women who took the antibiotic with a placebo. Among the probiotic group, 96% had high counts of protective bacteria recovered from the vagina at the one-month mark, versus 53% in the control group.
The strains used in that trial were Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14, taken orally twice daily for 30 days. These specific strains are available in commercial probiotic supplements. General “women’s health” probiotics may or may not contain them, so check the label for the exact strain designations (GR-1 and RC-14) rather than just the species name.
Be Cautious With Antibiotics
Antibiotics don’t distinguish between bacteria you want and bacteria you don’t. Uncontrolled antibiotic use is recognized as a factor that drives the vaginal microbiome away from a protective, stable state. If you’re prescribed antibiotics for an unrelated condition, you can’t always avoid them, but you can take steps to support your vaginal health during and after the course. Pairing antibiotics with the probiotic strains mentioned above is one evidence-backed approach. Avoiding douching and maintaining other protective habits during antibiotic treatment also helps minimize disruption.
What Raises Your Risk During Your Cycle
Menstrual blood has a pH of around 7.4, which is significantly higher than the vagina’s normal range. Each period temporarily raises vaginal pH, and this monthly fluctuation is one reason BV often appears or recurs around menstruation. You can’t prevent your period, but you can minimize additional disruptions during this vulnerable window. Changing tampons and pads frequently, avoiding scented menstrual products, and skipping douching after your period all help your vaginal environment recover its acidity faster.
Combining several of these strategies creates a compounding effect. A single habit change may not be enough on its own, especially if you’re prone to recurrence. But addressing semen exposure, product choices, smoking, and hygiene practices together gives your body the best chance of maintaining the acidic, protective environment that keeps BV from taking hold.