What are the different types of hair loss ?  
  Abnormal hair loss is of several types. Alopecia areata is when hair falls out in patches. In its most severe form, alopecia universalis, the individual loses all body hair including eyelashes, brows and pubic hair.


The most common form of hair loss in both men and women is known as androgenetic alopecia. Despite its standard name of "male pattern baldness" (MPB) it can also affect women and, is also the most common cause of hair loss.

Androgenetic alopecia develops as a gradual reduction of scalp hair follicle size, and reduced time in the "anagen" growth phase, leading to more hair follicles in the "telogen" resting stage of the hair cycle.