Both are common vaginal infections, but they aren’t considered sexually transmitted infections (STIs). Both of them also do not tend to have serious health consequences and can be successfully treated with antibiotics and even OTC medication (in the case of yeast infections).
Roughly one third of the females of reproductive age (15-49) in the U.S. get at least one BV outbreak per year, making it the most common vaginal infection. For yeast infection (‘vaginal candidiasis’ is the medical name but it’s more commonly known as ‘vaginal thrush’), the rate of occurrence in the U.S. female population is about 20%. Around one out of four women experience a yeast infection at least once in their lifetime.
So much for the similarities. Both infections vary in their causes and symptoms. BV often even is free of symptoms (in ~85% of cases), while symptoms are much more likely to develop with a yeast infection.
BV is caused by a bacterial imbalance in the vagina, which happens when ‘good’ bacteria are replaced with too many ‘bad’ bacteria. The good bacteria are called lactobacilli because they produce lactic acid that keeps the vagina slightly acidic and stops bad bacteria from entering. When there aren’t enough lactobacilli, the other bacteria take over. A bacteria called Gardnerella vaginalis usually is the first to do so, which is why BV sometimes also simply is called ‘Gardnerella’.
The most common causes of this bacterial imbalance are douching and using strongly scented soaps or vaginal wipes. These practices remove too many lactobacilli from inside the vagina, leaving it unprotected. Another major cause is sexual activity since it can introduce many harmful bacteria into the vagina, in addition to STI, of course. The transmission risk goes up if you have a new partner or regularly change partners. Sex between two women is just as big a risk factor as heterosexual activity.
Hormonal changes during menopause or pregnancy or the use of IUDs can also raise the risks of getting BV.
The only (and very noticeable) symptom of BV is a vaginal discharge that is grey or white and smells foul and fishy. As mentioned, most BV cases don’t develop symptoms and go away on their own unnoticed after a few days. However, if you develop the mentioned discharge, you’ll definitely notice it. A last note: BV doesn’t cause skin rashes, pain, or itching. If you experience such symptoms, the underlying problem won’t be a BV.
The culprit behind yeast infections isn’t a bacteria but a fungus called Candida. It occurs naturally in every woman’s vagina and usually doesn’t cause any problems as the lactic acid of the lactobacilli prevents the fungus from excessively growing and spreading. These are the same good bacterial forces that normally protect you from a BV. And just like with BV, it’s a bacterial imbalance — too few lactobacilli — that allows the yeast fungus to unleash its full growth potential and quickly spread all over the vagina.
As the fungus spreads, it causes an annoying itching sensation and mild to moderate during burning during urination. Other common symptoms include:
Note that yeast infections are associated with unpleasant odors. That’s one of the key differences with BV. Another is that yeast infections can give you a terrible itch, while you won’t really feel a BV.
Risk factors that can trigger a yeast infection include:
Yeast infections don’t easily go away on their own and will likely get worse or return if left untreated. That’s different from BV. So, if your symptoms and risk factors match the profile of a yeast infection, it’s always a good idea to seek medical help.
As mentioned, a BV normally disappears within about a week and often you can just wait it out, especially if you don’t have too strong symptoms and don’t feel uncomfortable. However, if you are pregnant or otherwise in a risk group, you should talk to your doctor. It may be necessary to treat the BV and speed up recovery, and prescription antibiotics usually are the preferred medication. Available antibiotic options are metronidazole and clindamycin, respectively as tablets or gel. For the toughest cases of BV, there also are suppositories that can be directly placed inside the vagina.
The antibiotic treatment process takes about one week, during which you should avoid alcohol and best also avoid or at least limit your sexual activity (use condoms if you can). Treatment usually successful, but in some patients, the BV can recur after a short period. If that happens more than once or twice, the reason may be that your partner may be transmitting it to you, although that’s rare. Your partner then can be tested and treated if necessary.
Yeast infections almost always require medical treatment, but fortunately, it’s relatively light medication, not antibiotics like in the event of a BV. There’s a range of antifungal creams, tablets or suppositories that target the candida fungus. Many of them even are available over-the-counter (OTC). After up to 3-4 days of use, the yeast infection will have disappeared.
Fluconazole (Diflucan) is one of the most popular antifungal medications for treating vaginal yeast infections and it comes as an oral tablet.
If it’s your first yeast infection, it’s advisable for you to schedule a follow-up inspection at your doctor to make sure that the infection has fully disappeared. Next time, if you are sure it’s a yeast infection, you sometimes can cure it out at home with OTC drugs. Of course, if you are pregnant or otherwise in a risk group, it’s best to see a doctor every time you get an infection.
Brown, Joelle M., et al. “Intravaginal Practices and Risk of Bacterial Vaginosis and Candidiasis Infection among a Cohort of Women in the United States.” Obstetrics & Gynecology, vol. 121, no. 4, Apr. 2013, pp. 773–780, 10.1097/aog.0b013e31828786f8. Accessed 16 May. 2020.
Cottrell, Barbara Hansen. “An Updated Review of Evidence to Discourage Douching.” MCN, The American Journal of Maternal/Child Nursing, vol. 35, no. 2, Mar. 2010, pp. 102–107, 10.1097/nmc.0b013e3181cae9da. Accessed 16 May. 2020.
Jacob, Louis, et al. “Prevalence of Vulvovaginal Candidiasis in Gynecological Practices in Germany: A Retrospective Study of 954,186 Patients.” Current Medical Mycology, vol. 4, no. 1, 29 July 2018, www.ncbi.nlm.nih.gov/pmc/articles/PMC6101156/, 10.18502/cmm.4.1.27. Accessed 16 May. 2020.