What is bacterial vaginosis?
Bacterial vaginosis (BV) occurs when the natural balance of bacteria in the vagina is disrupted — the healthy bacteria (lactobacilli) decrease and other bacteria overgrow. The main symptom is a thin, greyish-white discharge with a fishy odour, particularly after sex.
BV is not an STI. It's the most common vaginal infection in women of reproductive age, though many women have it without symptoms. It's different from thrush — thrush is caused by a yeast (fungal) overgrowth, while BV is caused by bacteria.
What causes it?
The exact cause isn't fully understood, but certain factors increase the risk: having a new or multiple sexual partners, douching, and smoking. The vaginal microbiome is delicate, and anything that disrupts it can allow BV to develop.
BV is more common in sexually active women but can occur in women who have never had sex. It's also more common with IUD use.
Treatment
BV is treated with antibiotics — usually metronidazole, taken as a tablet or as a vaginal gel. Treatment is effective, but BV can recur. About 30% of women experience a recurrence within three months.
If you think you have BV, see a GP. They can take a swab to confirm the diagnosis (as symptoms can overlap with thrush and other infections) and prescribe the right treatment. Avoid self-treating with thrush products — they won't work for BV.
Related condition
Vaginal & vulval health →References & sources
- 1.Vaginal thrush — healthdirect
- 2.Vaginal thrush — Better Health Channel
- 3.Bacterial vaginosis — Better Health Channel
- 4.Vulva and vagina — Jean Hailes for Women's Health
This content is general information and not a substitute for individual medical advice. Please consult a GP for your personal situation.
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