Patient Information for Vaginal Discharge Possibly Due to Bacterial Vaginosis
What is Bacterial Vaginosis?
Bacterial vaginosis (BV) is the most common cause of vaginal discharge and odor, occurring when normal healthy vaginal bacteria (Lactobacillus) are replaced by an overgrowth of other bacteria. 1 This is not a sexually transmitted infection, though it is associated with sexual activity—women who have never been sexually active rarely develop BV. 1
- About half of women with BV have no symptoms at all. 1
- BV can increase your risk for other infections and complications if left untreated. 1
- Treating your male partner does not prevent BV from coming back. 1
How is BV Diagnosed?
Your healthcare provider will diagnose BV by checking for at least three of these four signs (called Amsel criteria): 2, 3
- Thin, white-gray discharge that coats the vaginal walls evenly 2, 3
- Vaginal pH greater than 4.5 (measured with special pH paper) 2, 3
- Fishy odor, especially when a special solution (10% KOH) is added to a sample of discharge—this is called the "whiff test" 2, 3
- Clue cells seen under the microscope—these are vaginal cells covered with bacteria that have a distinctive stippled appearance 2
Your provider will perform a pelvic exam and test your vaginal discharge using pH paper and microscopy. 4, 3 If the diagnosis is unclear, additional testing like a Gram stain or molecular tests may be ordered. 2
Treatment
If you have symptoms, you need treatment with antibiotics. 1, 2 The main goal is to relieve your vaginal symptoms. 1, 2
Standard Treatment Options:
- Metronidazole 500 mg by mouth twice daily for 7 days (this is the preferred treatment with a 95% cure rate) 2
- Alternative: Metronidazole 2g by mouth as a single dose (lower cure rate of 84%) 2
- Alternative: Metronidazole vaginal gel or clindamycin vaginal cream 4
Important Points About Treatment:
- Complete the full course of antibiotics even if symptoms improve. 5 Poor adherence can lead to treatment failure. 6
- Avoid alcohol while taking metronidazole and for 24 hours after finishing it (can cause severe nausea). 5
- Your sexual partner does not need treatment. 1
What to Expect After Treatment
- BV has a high recurrence rate—50-80% of women experience it again within one year. 6, 7 This is common and does not mean the treatment failed initially.
- Return to your provider only if symptoms persist after treatment or come back within 2 months. 4
- If BV keeps recurring, your provider may recommend extended treatment: metronidazole 500 mg twice daily for 10-14 days, or metronidazole vaginal gel twice weekly for 3-6 months. 6
Why Treatment is Important
Even though BV may seem like just a nuisance, untreated BV can lead to serious complications: 1, 7
- Increased risk of acquiring HIV and other sexually transmitted infections 7, 8
- Pelvic inflammatory disease (PID) 1, 7
- Infections after gynecological procedures (like IUD placement, hysterectomy, or abortion) 1, 2
- If pregnant: increased risk of preterm birth and other pregnancy complications 1, 2
When to Seek Care
Contact your healthcare provider if: 4
- Symptoms do not improve after completing treatment
- Symptoms return within 2 months
- You develop new symptoms like fever, severe pelvic pain, or heavy bleeding
- You are pregnant and have vaginal discharge or odor
Prevention Considerations
While there is no guaranteed way to prevent BV, some factors may help: 7