Male pattern hair loss (androgenetic alopecia) is a hereditary condition distinguished by a receding hairline and the disappearance of hair from the top of the head, eventually balding a part (“bald spot”) or the entire top of the scalp. It is the most common type of hair loss in humans and affects millions of men worldwide.

Many believe that male pattern hair loss is inherited as a dominant trait from the maternal side of the family. However, the genetic predisposition for male pattern hair loss is more likely attributed to a combination of multiple genes (polygenic), the action of androgens (male sex hormones) and increasing age. Other than possible emotional or psychological effects (e.g., depression), male pattern hair loss poses no health risks.

In addition to taking a patient’s complete medical history and performing a physical examination, a physician diagnoses male pattern hair loss by observing the total amount of hair on the scalp and analyzing how it is distributed. Additional testing may be performed (e.g., skin biopsy, blood tests) to check if other diseases that cause hair loss (e.g., alopecia areata, telogen effluvium) are also present.

There is no cure for male pattern hair loss. However, medical and surgical treatments are available that may grow hair or prevent further hair loss (e.g., minoxidil, hair transplantation).