Thrush can be caused by a number of internal and external factors:
Thrush - Internal factors:
Poor health or diet: High sugar/yeast intake contributes to thrush by increasing urinary sugar.
Pregnancy: Hormone levels during pregnancy may create high levels of sugars in vaginal secretions.
Periods: Menstrual blood affects the vagina by changing the acidity or pH.
Diabetes: People with diabetes often have high blood sugar levels, including in their vaginal secretions.
Emotional or physical stress: stress may increase the risk of thrush as it affects your immune system, making you more vulnerable to thrush.
Thrush - External factors:
Sexual Intercourse: External stimuli may change the balanced environment of the vagina.
Perfumed soaps and bubble baths: These products may increase the risk of thrush as they increase the natural acidity (pH) of the vagina.
Wearing tight synthetic clothing: These can prevent the air from circulating and can create a warm, moist place for thrush to develop.
Antibiotics: Antibiotics kill friendly bacteria which keep yeast in the vagina under control.
Contraceptive pill: There is evidence to suggest that a high dose contraceptive pill can cause thrush.
Chemotherapy: Chemotherapy weakens your immune system, making you more prone to thrush.