Vaginal Infections (Vaginitis)

The three common vaginal infections compared

Bacterial vaginosis

Bacterial vaginosis (BV) is the most common cause of vaginal discharge in people aged 15 to 44. The normal protective lactobacilli are replaced by other bacteria. Risk factors include new or multiple sexual partners, douching and smoking. Many people have no symptoms. BV increases the risk of STIs, pelvic infections after procedures, and preterm birth in pregnancy. It recurs in about half of people within a year.

Vaginal yeast infection

Vaginal yeast infections affect about 3 in 4 women at some point. Itching, burning, redness and thick white discharge are typical. Risk factors include antibiotics, pregnancy, uncontrolled diabetes, a weakened immune system and high-estrogen contraceptives. Recurrent infections (4 or more a year) need testing to confirm the diagnosis and identify less common yeast species.

Trichomoniasis

Trichomoniasis is the most common curable sexually transmitted infection in the US. About 70% of infected people have no symptoms. It increases the risk of HIV and of pregnancy complications. Sexual partners must be treated, and retesting is recommended within 3 months.

Other causes of vaginitis

• Atrophic vaginitis (genitourinary syndrome of menopause): thinning, dryness, burning and pain with sex due to low estrogen
• Irritant or allergic vaginitis: from soaps, bubble baths, scented products, douches, spermicides, condoms or detergents
• Cervicitis from chlamydia or gonorrhea, which can cause discharge
• Desquamative inflammatory vaginitis: uncommon, with purulent discharge
• Foreign body, such as a forgotten tampon, causing foul discharge
• Vulvovaginitis in girls: often from irritation or poor hygiene; persistent cases need assessment

Normal vs abnormal discharge

Normal discharge is clear to white, does not smell bad, and changes in amount and texture through the menstrual cycle. See a provider if discharge changes color, consistency, amount or smell, or comes with itching, burning, pain or bleeding. See vaginal discharge.

Diagnosis

A healthcare provider will ask about symptoms, sexual history, recent antibiotics and products used, then may:

• examine the vulva, vagina and cervix
• measure vaginal pH with a test strip
• look at a sample under the microscope (wet mount) and do a "whiff test"
• send a swab for nucleic acid amplification tests (NAATs) for BV, yeast, trichomoniasis, chlamydia and gonorrhea
• do a culture for recurrent yeast infections

Self-collected vaginal swabs are accurate and acceptable for many tests.

Treatment

• Bacterial vaginosis: oral or vaginal metronidazole, or clindamycin cream, or other options such as secnidazole. Avoid alcohol with metronidazole and for the time recommended afterward
• Yeast infection: over-the-counter vaginal antifungals (miconazole, clotrimazole) for 1 to 7 days, or a prescription single dose of oral fluconazole. Oral fluconazole is avoided in pregnancy; vaginal treatment for 7 days is used instead
• Trichomoniasis: oral metronidazole (a 7-day course is recommended for women), with treatment of all sexual partners and avoiding sex until both have finished treatment and symptoms are gone
• Atrophic vaginitis: vaginal moisturizers, lubricants and low-dose vaginal estrogen
• Irritant vaginitis: stop the irritant and use plain water for washing

Recurrent BV or yeast infections may need longer suppressive treatment.

Prevention

• Avoid douching, scented soaps, sprays and bubble baths
• Wash the vulva with plain water or a mild unscented cleanser
• Wear breathable cotton underwear and change out of wet clothing promptly
• Use condoms to reduce STIs and BV
• Wipe front to back
• Control blood sugar if you have diabetes
• Take antibiotics only when needed

Frequently asked questions

What are the most common vaginal infections?

The three most common are bacterial vaginosis, vaginal yeast infection and trichomoniasis. Together they cause most cases of vaginitis. Thinning of vaginal tissue after menopause and reactions to irritants are other common causes.

How do I know if it's BV or a yeast infection?

BV usually causes thin, gray-white discharge with a fishy smell and little itching. Yeast infections cause thick, white, clumpy discharge with intense itching and redness but little odor. Because they overlap, a test is the most reliable way to tell.

Can vaginal infections go away on their own?

Mild BV sometimes clears without treatment, but it often returns, and treatment is recommended if you have symptoms or are pregnant. Yeast infections and trichomoniasis generally need treatment. Untreated infections can raise the risk of other problems.

Are vaginal infections sexually transmitted?

Trichomoniasis is sexually transmitted, and partners need treatment. Bacterial vaginosis is linked to sexual activity but is not considered an STI. Yeast infections are not sexually transmitted. Chlamydia and gonorrhea can also cause discharge and should be tested for.

When should I see a doctor for vaginal discharge?

See a provider for a first episode, symptoms that do not improve with over-the-counter treatment, recurrent infections, pregnancy, possible STI exposure, or discharge with fever, pelvic pain, bleeding or sores.