Recurrent thrush and bacterial vaginosis

Two of the most common reasons for vaginal symptoms are routinely confused with each other, and treating one as the other reliably makes things worse.

The difference

Thrush is an overgrowth of candida, a yeast that lives normally in the vagina in many people.

Its characteristic symptoms are itching, soreness, and a thick white discharge that is typically not malodorous.

Bacterial vaginosis is a disturbance of the vaginal bacterial community, with a reduction in protective lactobacilli and an overgrowth of other organisms.

Its characteristic symptoms are a thin grey or white discharge with a distinctive fishy odour, frequently worse after sex, and typically without significant itching.

Studies of self-diagnosis have repeatedly found that women buying over-the-counter thrush treatment are frequently treating something else — bacterial vaginosis, trichomonas, a skin condition or an unrelated infection.

Which matters, because antifungal treatment does nothing for bacterial vaginosis and delays the correct treatment.

Why bacterial vaginosis matters more than its symptoms suggest

It is associated with increased susceptibility to sexually transmitted infections including HIV, with pelvic inflammatory disease, and in pregnancy with preterm birth.

Which is why it is worth diagnosing and treating properly rather than managing with deodorising products.

It is not classed as a sexually transmitted infection, though sexual activity influences it, and research into whether treating male partners reduces recurrence has produced interesting recent results.

What makes recurrence more likely

For bacterial vaginosis: douching, which is the single clearest modifiable factor and which is actively harmful; scented products, bath additives and washes used internally; smoking; new or multiple partners; and copper intrauterine devices in some cases.

For thrush: antibiotics, which clear the competing bacteria; poorly controlled diabetes, which should be considered in anyone with frequent episodes; immunosuppression; pregnancy; some hormonal contraception; and high-oestrogen states.

Tight synthetic clothing and prolonged dampness are commonly blamed and the evidence is weaker than the folklore.

Vulval care, which prevents a great deal

The vagina is self-cleaning and requires nothing internally.

Wash the vulva with water or a plain emollient, not soap, shower gel, bubble bath or anything fragranced.

Do not douche, ever, under any circumstances.

Avoid feminine hygiene products entirely — they treat a normal odour as a problem and disturb the environment that prevents actual problems.

Wipe front to back.

Change out of wet swimwear and sweaty clothing reasonably promptly.

And use a plain emollient as a barrier if the skin is prone to irritation.

Treatment

Thrush responds to topical antifungal pessaries and creams or an oral tablet, with similar effectiveness.

Recurrent thrush — four or more episodes a year — is treated with an induction course followed by maintenance over months, which is considerably more effective than repeatedly treating individual episodes.

Bacterial vaginosis is treated with specific antibiotics, oral or vaginal, and recurrence within a few months is common.

Longer suppressive regimens are used for frequent recurrence.

Note that antifungal creams damage latex condoms and diaphragms, and that some antibiotics used for bacterial vaginosis interact badly with alcohol.

When it is not either of them

The reason a proper diagnosis matters.

Trichomonas is a sexually transmitted infection with similar discharge and requires different treatment and partner notification.

Chlamydia and gonorrhoea can cause discharge and frequently cause nothing.

Skin conditions — eczema, lichen sclerosus, lichen planus — cause itching and soreness and are missed for years, and lichen sclerosus in particular requires treatment because of its long-term implications.

Allergic and irritant contact dermatitis from products, wipes, lubricants, and washing powder is very common.

Genitourinary changes of menopause produce dryness, irritation and susceptibility to infection.

And any persistent vulval lesion, ulcer or change in appearance needs examination rather than treatment by guesswork.

What to do about recurrence

Get a diagnosis confirmed at least once, with swabs, rather than assuming.

Check for diabetes if thrush is frequent.

Review products and stop everything fragranced.

Ask about maintenance regimens rather than repeated single courses.

Consider whether symptoms are actually a skin condition, particularly if itching persists between episodes.

And be sceptical of the large market in probiotic and boric acid preparations, where evidence exists for some uses and is far weaker than the marketing suggests.

General information only, not medical advice. Consult a qualified clinician for diagnosis of vaginal symptoms rather than relying on self-diagnosis.