The dark color of hairs is due to presence of pigment called malanine. In the absence of this hairs become Grey. Diet also play major role in the development of this condition. It is also hereditary to have Grey hairs early or late.
Why Do Women Get Grey Pubic Hairs?
Women get grey pubic hairs for the same reason men do: They get old. Pubic hair goes grey just like head hair, and for the same reason.