The hair on your scalp is terminal hair, but its also found on other areas of the body.
Terminal hair is one of the two types of hair that children and adults have.
The other, vellus hair, differs from terminal hair in several ways.
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Duringpuberty, increased hormone levels cause vellus hair to turn into terminal hair in certain areas.
Not all body hair is the same, though.
Vellus hairis the thin, short, soft, peach-fuzz-like hair that covers most of the human body.
DermNet /CC BY-NC-ND
It replaces lanugo, an even softer, thinner punch in of hair found on babies in utero.
Lanugo may also be present for the first few weeks after birth.
Vellus hair is thought to primarily serve as insulation for the body.
Terminal hair is known as mature hair.
Its thicker and grows longer than vellus hair.
During puberty, hormones will change some vellus hair follicles into terminal hair follicles.
Androgens, a group of sex hormones released during puberty, trigger these changes.
Different parts of the body are especially sensitive to these hormones.
In contrast, they are essential in male physical and sexual development.
During these years, both boys and girls grow terminal hair under the arms and in the pubic areas.
In fact, in the early stages of puberty, terminal hair growth is concentrated in the pubic area.
The pituitary gland secretes hormones that initiate puberty, including luteinizing hormone, androgens, andprogesteronein females.
If these hormones aren’t being secreted, puberty cannot occur.
Several disorders can also cause delayed puberty which will affect hair growth.
These conditions include:
In some cases, terminal hair doesn’t grow at all.
Genetics are most often to blame for these incidents.
What Is Luteinizing Hormone?
Luteinizing hormone is made in the pituitary gland.
It stimulates the release of estrogens from the ovary in women and testosterone from the testicles in men.
Premature Growth
In some cases, terminal hair begins to grow earlier than normal.
Specifically, hormonal changes that are more prevalent as you age will affect hair growth on the head.
Most of the body is not affected by these hormonal changes.
Researchers believe there is a genetic component that results in a change in how androgens affect the hair follicle.
It is less common in women, but among women over 70, 38% have the condition.
Thicker, coarser hair is known as terminal hair.
Both boys and girls develop terminal hair in the pubic area and under the arms.
Boys will also develop facial hair and thicker hair on other areas of the body.
Certain genetic factors and medical conditions can result in terminal hair developing earlier or later than usual.
As adults age, hormonal changes once again affect the growth of terminal hair.
This can result in male-pattern baldness, which affects females as well as males.
Medication can help reduce the amount of hair you lose from this condition.
A Word From Verywell
Hair growth around the genitalia is one of the first signs of puberty.
If terminal hair doesn’t appear until the teen years, don’t worry.
This too can be normal, especially if other family members hit puberty a little late.
However, be sure to talk to your pediatrician about any signs of delayed growth.
As adults age, concerns about terminal hair loss may affect self-esteem or self-image.
Frequently Asked Questions
Vellus hair is softer, thinner, and lighter than terminal hair.
It’s believed to help keep the body warm.
However, many children do not develop pubic hair until later in puberty.
During puberty, hormones will naturally turn some vellus hairs into terminal hairs.
Hair in the pubic area grows for only a few months before making transitions and eventually shedding.
(In contrast, head hair grows for two to six years.)
Less time growing means pubic hair tends to remain short.
There arehair folliclesall over the body.
Within the follicles are stem cells, blood vessels,sebaceous glands, and, of course, hair.
The follicle lies within the secondlayer of the skin: thedermis.
This is the living part of the hair.
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