This moisture may be perspiration, urine, vaginal discharge or small amounts of stool.
It may be caused by vaginal infections, vulvitis, HPV (human papilloma virus) infection, anal incontinence, Bowen's disease, or dietary irritants (caffeine, potatoes, chilli, capsicum, tomatoes, and peanuts).
Treatment with antibiotics can lead to a yeast infection and irritation of the vulva.
Some diseases increase the possibility of yeast infections, such as diabetes mellitus.
Chronic inflammation of the vulva predisposes to the development of premalignant or malignant changes.