The Hair Growth Cycle

If you’re exploring hair transplant procedures, you’re likely wondering how soon you’ll start seeing new hair growth. We’re here to help you understand the various stages of the hair growth cycle. In fact, the hair growth cycle after a hair transplant is similar to the stages of hair growth for normal hair. The reason is that donor hair is taken from the back of the scalp and transplanted to balding or sparse areas where hair loss is occurring. Below is an overview of the four distinct phases of the hair growth cycle and how the cycle begins and continues after a hair restoration procedure.

The Anagen Phase

The anagen phase is also known as the hair growth phase. It’s the longest phase of the hair follicle growth cycle lasting between two to six years. However, as we age, this stage shortens over time. Hair in this stage also loses thickness and pigmentation. The rate at which hair grows depends on several factors and varies from person to person. But, the American Academy of Dermatology reports that, on average, hair grows a 1/2 inch per month. 

The dermal papilla is the most important part of the hair follicles and contains blood vessels and hair growth regulating cells, playing a key role in the hair growth cycle. The blood vessels deliver essential vitamins and nutrients to each hair follicle and hair shaft.

If you have a genetic condition that causes hair loss, such as alopecia areata or androgenic alopecia (male pattern baldness), it can result in a shorter anagen phase and resulting in hair thinning or produce shorter hair. Each hair follicle is at different points in the anagen phase (or another phase in the hair growth cycle), and the anagen phase may continue to decrease over time. It’s the reason why, for many, hair is lost gradually over many years.

The Catagen Phase

In contrast to the anagen phase, the catagen phase is the shortest and lasts approximately two weeks. This stage is a transitional phase marking the end of active growth before the hair follicle begins the resting or telogen phase. What happens during the catagen phase: The hair shaft or hair bulb at the bottom of the hair follicle detaches from the blood supply and shrinks. The hair separates from the bottom of the hair follicle but remains in place. Hair growth may continue but at a much slower pace. The hair becomes a club hair before it transitions to the telogen phase. Approximately 3-5% of the hairs on your head are in the catagen phase at any given time.

The Telogen Phase

The telogen phase is also known as the hair resting phase. The hair follicle rests for 3-5 months before it starts the growing phase again. The blood supply has been cut off from the hair, and it has stopped growing. However, the follicle will begin to grow a new strand of hair over the old hair. Approximately 10-15% of your scalp hair is in the telogen phase at any given time.

A hair loss condition that can occur during the telogen phase, Telogen effluvium, results in rapid hair shedding and is stress-induced. It can be caused by emotional or physical stress such as illness, trauma, or chronic illness. Often, telogen effluvium is temporary, and the hair follicles begin hair regrowth in the anagen phase.

The Exogen Phase

The exogen phase is the shedding phase of the hair growth cycle. It’s frequently considered an extension or a part of the telogen phase of the hair growth cycle. Old hairs fall out as new hairs continue to grow in the follicle. A healthy scalp will shed 50-100 hairs per day. The exogenous phase can last for 2-5 months.

How Long Is the Hair Growth Cycle?

Hair Growth Cycle

As we discussed, human hair growth and shedding happen randomly, and 85-90% of our scalp hair is in an active growth cycle at any time. The hair growth cycle for each hair lasts between 3 and 7 years, and then the cycle restarts again.

How Does Hair Grow After 
Hair Transplant Surgery?

Phase 1: The Exogen Phase

After a hair transplant, the first stage of the hair growth cycle you’ll likely experience is the exogen stage. After approximately two weeks, hair falls out of the transplanted follicles. This event is known as shock loss and completely normal after a hair transplant. The follicles temporarily lose their blood supply and undergo stress after grafting. This shedding period may last 3-4 months.

Phase 2: The Anagen Phase

Once the transplanted hair sheds and the hair follicle rests in its new location, the anagen phase begins again. In this phase of hair growth, the transplanted follicles should start producing hair. The hair is fine or thin at first and will thicken over time. Just like the other hair follicles on your scalp, transplanted follicles will continue to produce healthy hair strands for 2-6 years. The new hair will continue to grow as it did in the original location at a rate of approximately a 1/2 inch per month. Once the hair starts growing, you’ll get a sense of the amount of fullness (or density) the hair transplant has provided. In some cases, another hair transplant may be needed to reach the desired density of hair. Most patients will see full results one year after hair transplant surgery.

Phase 3: The Catagen Phase

The third phase of the hair growth cycle after a hair transplant is the catagen phase. Similar to other hair growth, this phase lasts two weeks or more and is the transition phase when active hair growth ends and slows considerably. The hair detaches from the hair follicle but remains attached to the scalp.

Phase 4: The Telogen Phase

This final phase after a hair transplant surgery occurs as it does with normal hair. Known as the resting phase, hair stops growing and prepares to shed. A new hair strand begins to grow over the old hair strand in the follicle.

Hair transplant surgery is a permanent solution to hair loss, and the transplanted hair will continue to the hair growth cycle for the rest of your life!

How to Increase the Anagen Phase of Hair

Hair growth stages

Healthy hair growth depends on various factors, including age, genetics, and hormone levels. While these factors are mostly out of your control, maintaining a healthy lifestyle and proper hair care can increase the likelihood you will have healthy, fuller hair. Approaches to improve hair growth during all four phases of the hair growth cycle include:

Hair growth treatments and hair transplants are most effective when the hair follicles are still active and in the early stages of hair loss.

Get in Touch with Lumen to Schedule a No-Obligation Consultation

If you’re noticing excess shedding, balding or sparse areas of thinning hair, contact The Lumen Center for a free, no-obligation hair and scalp consultation. We discuss details of our comprehensive hair restoration process, answer your questions, and determine the best course of action for treating your hair loss. We customize treatment plans to your unique situation and hair growth goals. 

Dr. Andrew Kwak and his expert team will be with you every step of the way – from consultation to multiple touchpoints post-procedure for a highly personalized approach to care. Take the first step to regain healthy hair and contact us today at 610.525.0606 to book your consultation.