Bacterial Vaginosis: An Overview
Bacterial vaginosis, usually shortened to BV, is the most common vaginal condition in women of reproductive age, yet many women have never heard of it. It happens when the normal balance of bacteria in the vagina tips, with friendly lactobacilli losing ground to other types. For most women it is simply an annoying discharge; for a few, especially during pregnancy, it deserves careful attention. Here is what you need to know.
What is bacterial vaginosis
The vagina naturally contains many types of bacteria, and a healthy environment is dominated by lactobacilli, which keep the pH acidic and hostile to other organisms. In BV, those protective bacteria decline and other bacteria multiply, which shifts the pH and produces the classic symptoms. BV is not an infection passed between partners in the usual sense, and it is not the same as thrush, even though the two are frequently confused.
The symptoms
Many women with BV notice nothing unusual. When symptoms appear, the most common is a change in discharge: thin, watery, greyish-white and with a noticeable fishy smell that is often stronger after sex or around a period. Unlike thrush, BV is not usually itchy or sore, and thrush needs a different treatment entirely.
| What you might notice | Bacterial vaginosis | Thrush |
|---|---|---|
| Discharge | Thin, watery, greyish-white | Thick, white and curd-like |
| Smell | Strong fishy odour | Usually little or no smell |
| Itching | Rarely | Often intense |
| Main feeling | Discharge and odour | Itch and soreness |
Causes and risk factors
Anything that disturbs the vaginal pH can trigger BV. That includes new or multiple sexual partners, using scented soaps or shower gel on the area, washing inside the vagina, and smoking. Hormonal changes such as pregnancy and the menopause can also play a part. It is not caused by poor hygiene, and no amount of extra washing will clear it; in fact, washing inside the vagina tends to make it worse.
Why treatment matters
Left alone, BV often clears by itself, but treatment is still worth having. It resolves the discharge and odour, reduces the risk of catching sexually transmitted infections, and matters most in pregnancy, where it has been linked to premature labour. If you are pregnant and think you might have BV, mention it so it can be checked rather than assuming it will pass.
How BV is treated
BV is treated with antibiotics, which in the UK are available only after a proper assessment with a GP, a sexual health clinic or a registered online pharmacy consultation. Treatment is usually a metronidazole gel applied inside the vagina, clindamycin cream, or metronidazole as tablets. Avoid alcohol with metronidazole tablets, and complete the full course even if symptoms settle quickly, because stopping early makes recurrence more likely.
Preventing recurrence
BV has a genuine tendency to return, and a minority of women have it again and again. Steps that help include plain, unperfumed products on the vulva, not washing inside the vagina, and finishing every course of treatment. Some evidence supports a probiotic containing lactobacilli to help restore the balance. If episodes keep returning, a review can look for underlying causes and discuss longer or repeated courses. Always check with a pharmacist or GP before starting anything new.
When to see a GP
See a doctor if this is your first episode, if the smell is new, if you are pregnant, or if treatment has not worked. You should also be tested if you are in a group at higher risk of sexually transmitted infections, since BV makes that risk greater. Understanding why urinary infections differ can also help you describe symptoms accurately at an appointment.
BV is common, harmless for most women and straightforward to treat. Knowing what it is, recognising it correctly and completing treatment fully is usually all it takes to put it behind you.