Each culture of human society developed social norms relating to the presence or absence of body hair, which has changed from one time to another. Different standards of human physical appearance and physical attractiveness can apply to females and males. People whose hair falls outside a culture's aesthetic standards may experience real or perceived social acceptance problems, psychological distress and social difficulty. For example, for women in several societies, exposure in public of body hair other than head hair, eyelashes and eyebrows is generally considered to be unaesthetic, unattractive and embarrassing. In Middle Eastern societies, removal of the female pubic hair has been considered proper personal hygiene, necessitated by local customs, for many centuries.