Laser Technician (International Board of Electrologist Certification) IBEC Board Exam

Which stage of hair growth is characterized by the transition from the anagen phase to the telogen phase?

1. Catagen

2. Anagen

3. Telogen

4. Exogen

The correct answer is: Catagen

The stage of hair growth that marks the transition from the anagen phase to the telogen phase is known as catagen. During the catagen phase, which is a short transitional phase lasting a couple of weeks, the hair follicle begins to shrink, and hair growth stops. This phase is essential because it prepares the hair for shedding and is when the hair detaches from the blood supply and is no longer nourished by the follicle. The anagen phase is the active growth phase, where the hair is cultivated and nourished, leading to increased length. Conversely, the telogen phase is the resting phase, where hair remains in the follicle without growing and ultimately prepares for shedding. The exogen phase refers to the process of shedding the hair that has completed its lifecycle. Understanding these phases helps in recognizing the natural hair growth cycle necessary for various hair treatment techniques, including those used in laser therapy.