Hair grows out of a bulb-like root, connected to and fed by hair follicles. Follicles are located approximately 1/8 inch below the surface of the skin. It takes effort to pull a single hair free from its follicle. It takes even more to remove a whole patch of hair simultaneously. Most cases involving patches of hair, rather than single strands of hair, are due to trauma, injury or accident.
The possibilities of regrowth after a traumatic event are left up to chance. While in all likelihood your hair will grow back, it is possible that all or some of your hair follicles were damaged enough in the incident to make new growth impossible. You should start to see fine hair growth approximately two weeks after the incident. In some cases, injury prevents the follicles from reproducing hair quickly. When this occurs, hair growth is temporarily halted until the follicles heal. Generally, if hair has not started to grow back after three months, the possibility that it might grow back in the future is minute.
New hair growth is fine and downy. While you may not be encouraged by peach fuzz, its presence indicates better things for your hair in the future. Downy growth precedes all new hair growth and indicates that the follicles are not dead and will produce new hair.
Fragile new growth should be treated with the utmost care. Do not pluck or tweeze new growth. Avoid placing any tension on the new hair when styling your hair. All chemical hair services should be avoided at this point.
After three months, hair begins to thicken and resemble the original patch of hair that was pulled out. Styling may still be difficult due to the short length of the hair. The length of new growth three months out averages between 1 and 2 inches, based on an average growth of ½ inch per month. Your hair may grow faster or more slowly, depending on your genetic makeup.
You may also notice that the new growth is thinner in density than the hair growing around it. While common, thinner hair indicates that some follicles were damaged. As your hair grows, the thin spot will become less noticeable.
After five months have passed, chemical services are no longer off limits. The new growth should measure 2 to 3 inches, or longer. Now is the time to start thinking about blending in the shorter patch with a new haircut or style.
After seven months, you and others should not be able to tell that you have lost hair in the past. While the new growth may still be shorter than the rest of your hair, it will blend nicely. Length at this stage averages 3 to 4 inches, or longer.
- ScienceRay: I Am Your Hair: Anatomy, Physiology and Growth
- "Milady's Standard Textbook of Cosmetology"; Milady, Diane Carol Bailey and Margrit Attenburg; 2008