All you need to know about thrush
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How does the yeast infection occur?

Normally, there is a delicate balance between bacteria and yeasts that live naturally within the vagina. However, this balance is easily upset by any of the following factors which could allow the yeasts to overgrow, leading to thrush infection.

Internal factors that cause thrush

Poor health or diet: 

For example food such as sugar, dairy products, coffee, tea and wine contribute to thrush by increasing urinary sugar which in turn encourages the growth of yeast in the vagina.   


These may increase the growth of yeast as antibiotics kill friendly bacteria which keep yeast in the vagina under control. Also the underlying illness may cause the body to weaken, giving yeast the opportunity to multiply more easily.


Hormone levels during pregnancy may create high levels of sugars in vaginal secretions, which result in the growth of yeast in the vagina.  


Menstrual blood affects the vagina by changing the acidity of the vagina. Tampons and towels may also increase the chance of thrush especially if tampons are kept in too long as they will also change the pH balance of the vagina. Towels also provide a moist and warm environment for yeast to multiply.


As diabetes increases blood sugar levels including in the vaginal secretions. Diabetic women also tend to have high sugar levels in their urine and this may contribute to thrush by feeding yeast in the genital area just outside of the vagina.  

Contraceptive Pills:

There is a chance that a high dose contraceptive pill may also cause thrush while there is no evidence that a low dose contraceptive pill causes thrush.

Emotional or physical stress:

Stress may increase the risk of thrush as it affects your immune system and in turn making you more vulnerable to thrush.  


Chemotherapy weakens your immune system, making you more prone to thrush.  

External factors that cause thrush

Sexual Intercourse:

External stimuli may change the balanced environment of the vagina and in turn lead to the growth of yeast in this area.  

Perfumed soaps and bubble baths:

These products may increase the risk of thrush as they increase the natural acidity (pH) of the vagina or damage the tissues.

Wearing tight synthetic clothing:  

Prevent air from circulating and can create a warm, moist place for thrush to develop.


Helpful Tips

• Avoid tight, synthetic clothing; loose, cotton knickers may help

• Avoid perfumed soaps, gels and bubble baths and vaginal deodorants