The prevalence of upper lip hair in black and white girls during puberty: a new standard.

In order to develop standards for upper lip hair in adolescent girls, 4693 observations in 856 black and white subjects were made over 9 years. Up to 2 years after menarche, 90% of girls had no upper lip hair. More than 2 years after menarche, 48.8% of black girls and 9.0% of white girls had small amounts of upper lip hair. This may be more significant in adolescent girls than in older women.