Androgenetic Alopecia (Inherited Hair Loss)

Androgenetic alopecia is a type of hair loss that is inherited from either or both the mother and the father. Also known as male- or female-pattern hair loss, it is the most common cause of hair loss.

The condition occurs when the growth (anagen) phase of the hair growth cycle becomes shorter and shorter. A genetic sensitivity to androgens, a type of hormone, causes hair follicles—where hair growth begins—to sprout hairs that are thinner than normal. The hairs become thinner and thinner, and eventually the follicles die away.

  • In men, hair loss occurs on the front hairline and forehead and on the top of the head. Bald spots are noticeable.
  • In women, hair loss occurs as thinning of hair on the top of the head. Women tend to keep their front hairline and do not generally develop bald spots.

Last Revised: May 29, 2012

Author: Healthwise Staff

Medical Review: Adam Husney, MD - Family Medicine & E. Gregory Thompson, MD - Internal Medicine

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