It has been noted that a high proportion of women with high hairlines are descendants of peoples of Africa, the British Isles or China. Although I have not reviewed any published statistics on this, it has been my clinical observation for the past 30 years. Of course, high hairlines are seen in women from a wide variety of ethnic backgrounds.
A notable group of women who have high hairlines are African Americans who have a combination of hereditary factors and traumatic factors from straightening the hair and pulling it back, therefore, at times pulling out the weaker hairs in the front and the temples. Usually there is a history of straightening the hair and pulling it tightly back in various hairstyles, i.e., weaves, corn rows, tight braids, buns or use of hair extensions. One should note that in almost every predominantly African American neighborhood, there are a disproportionate number of women’s wig stores which cater to African- American women many of whom want to have the appearance of a full head of hair.
A good source of information is seen in the comedy-documentary movie by Chris Rock (2009), Good Hair.
I recommend viewing it.
If the condition is not too severe, these women can be treated with transplants or hairline lowering procedures. Lately I have been seeing more candidates for hairline lowering who have flexible scalps and adequate remaining hair to bring down. Also we are doing more grafting transplant procedures for sparse temple hair.