Bacterial vaginosis (BV) is a common vaginal infection caused by an imbalance in the normal bacterial flora of the vagina, characterized by an excessive growth of certain bacteria, especially anaerobic bacteria like Gardnerella vaginalis. It typically leads to symptoms such as increased vaginal discharge that is thin, gray or white in color, often with a strong fishy odor. Burning during urination may also occur, while itching is less common. In some cases, BV may cause no symptoms. BV is not considered a sexually transmitted infection, though sexual activity and factors such as douching, multiple partners, and not using condoms increase the risk. It can raise the risk of acquiring sexually transmitted infections and complications during pregnancy. Diagnosis is based on symptoms, vaginal discharge examination, and pH testing. Treatment usually involves antibiotics like metronidazole or clindamycin, but recurrence is common. Probiotics may help prevent recurrence, though their effect on pregnancy is unclear.
Key Characteristics
- Caused by imbalance of vaginal bacteria, mainly decreased lactobacilli and overgrowth of anaerobic bacteria including Gardnerella vaginalis.
- Symptoms: thin gray or white discharge with a fishy smell, possible burning with urination.
- Often asymptomatic in many women.
- Increased risk of STIs and pregnancy complications.
Risk Factors
- Sexual activity with new or multiple partners.
- Douching and use of intravaginal hygiene products.
- Not using barrier contraception (condoms).
- Smoking and other lifestyle factors.
Diagnosis and Treatment
- Diagnosis by clinical signs plus lab tests including vaginal pH and microscopic examination.
- Treatment with antibiotics such as metronidazole or clindamycin.
- Recurrence is common; probiotics may help prevent it.
- Pregnant women with BV need careful management due to risks.
Bacterial vaginosis is the most common vaginal infection in reproductive-aged women, affecting about 23–35% globally depending on demographic factors.
