A yeast infection is caused by a fungus and tends to be recurrent given certain conditions. It's a very common complaint in women, and usually affects warm, moist parts of the body, in particular the vaginal area. This kind is known as vulvovaginal candidiasis or vaginal thrush.

It is believed that an estimated 20 to 50 per cent of healthy women carry yeast normally. Candida, the name of the fungus that causes the infection, can overgrow as a result of stress, pregnancy and illnesses that affect the immune system. Certain medications like some types of birth control pills, steroids and antibiotics can also cause yeast infections.

Many women are affected after using antibiotics, which act by killing the "good" bacteria that live in the body, bacteria which help to keep the growth of candida in check. Others on the pill may see increased incidences especially after first starting, and it is believed that women with diabetes that isn't controlled are at a higher risk for yeast infections.

Dr Sharmaine Mitchell, obstetrician and gynaecologist, said yeast infections also tend to be recurrent in HIV positive women and those with systemic lupus.

The condition presents with a thick, creamy, white discharge that tends to cause itching of the vagina, vulva and sometimes groin regions.

If the condition is not properly treated, the problem will not be resolved.

Yeast infections are treated with antifungals which may be given in the form of tablets by mouth, vaginal pessaries, creams or gels. Over-the-counter treatment is available in Monistat, while other drugs are available by prescription only.

It is advised that if women with recurring yeast infections are sexually active, that their partners be treated to reduce the risk of re-infections. You should also be tested for diabetes mellitus and HIV as if you are immunocompromised in any way this can lead to recurrent infections.

"Men tend not to show any signs of an infection even though the bacteria or fungus is present and so treatment is necessary despite the lack of symptoms," Dr Mitchell said. She said women can reduce the risk of reinfection by ensuring their underwear get adequate sunlight — avoid hanging them in shaded areas in the bathroom.

The use of gentian violet to paint the inside of the vagina can sometimes help in resistant cases, Dr Mitchell said.

Other ways to prevent yeast infections, according to womenshealth.gov, an online project of the US Department of Health and Human Services Office, are:

*Avoid douches.

*Avoid scented hygiene products like bubble bath, sprays, pads, and tampons.

*Change tampons and pads often during your period.

*Avoid tight underwear or clothes made of synthetic fibres.

*Wear cotton underwear and pantyhose with a cotton crotch.

*Change out of wet swimsuits and exercise clothes as soon as you can.

*Avoid hot tubs and very hot baths.