Hirsutism
Coarse, dark hair growth in a male-pattern distribution, such as the chin, upper lip, and lower abdomen. One of the most evidenced androgenic signs.
Hirsutism is the growth of coarse, dark, terminal hair in areas where it follows a male-pattern distribution: the chin, upper lip, jawline, chest, and lower abdomen. It is different from the fine, pale vellus hair that everyone has across most of the body.
It happens because hair follicles in these regions carry androgen receptors. When free testosterone is elevated, those follicles switch from producing fine hair to producing terminal hair. Most of the driving androgen is ovarian, with a smaller adrenal contribution in some people.
Hirsutism is one of the most reliable clinical signs of hyperandrogenism, and clinicians sometimes score it formally (the Ferriman-Gallwey scale) to track it. Because the driver is hormonal, approaches that lower androgen load or improve insulin sensitivity can help over time, alongside the cosmetic options many people use day to day.