Terminalhaaren

Terminalhaaren are thick, pigmented hairs on the human body that replace finer vellus hairs in certain regions. They are longer, coarser, and darker than vellus hairs and are better anchored in the skin. Terminal hair is most noticeable on the scalp, eyebrows, eyelashes, the armpits (axillae), the pubic region, and often the beard area in men; in women the distribution is variable and generally lighter but can extend to similar regions under hormonal influence.

Origin and development: The transformation of vellus into terminal hair is largely driven by androgens, especially during puberty; genetic and ethnic factors influence where terminal hair appears and how dense it becomes. There are also racial differences in hair types and patterns.

Growth cycle: Terminal hairs, like other hairs, go through cycles: anagen (growth), catagen (transitional), and telogen (rest). Terminal hair has a longer anagen than vellus hair, enabling greater length. The cycle length and thickness vary by body site and individual.

Clinical notes: Normal variation in terminal hair density exists; excessive terminal hair growth in women or in unusual areas is called hirsutism and may signal hormonal imbalance or medical conditions such as polycystic ovary syndrome. Age-related changes can also alter terminal hair patterns.