Why does facial hair grow on guys and not most girls?

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Question: Why does facial hair grow on guys and not most girls?

Answer: All girls have facial hair, but it’s very soft and faint compared to that of boys. Gaining facial hair, for boys and girls both, is one of the last changes that come with puberty. Most boys start noticing hair on their faces at age 15 or 16. The reason that facial hair is so much more dominant in males than females is due to chemicals called androgens, one of which is testosterone, a male sex hormone.

Males have much more testosterone than females; hence, they grow much more facial hair. Biological females who identify as transgender sometimes undergo masculinizing hormone therapy, in which large amounts of testosterone are introduced into their bodies. Over time, they, too, develop heavier facial hair.

Ironically, the same androgens which cause males to produce thick facial hair can trigger, later in life, the exact opposite effect, particularly on top of male heads. Hence, the widespread affliction known as male pattern baldness.