Vaginal thrush affects many women at some point in their adult lives, most commonly  during childbearing years, and may recur regularly. The condition develops when a fungus called Candida albicans, which can occur naturally in the vagina, grows more rapidly than usual. Vaginal thrush is not serious, but it may cause unpleasant itching of the vulva and vagina and a discharge. Candida infections may occur in other areas, such as the mouth (Oral thrush).