use the terms hair loss and alopecia interchangeably.
Hair loss may be divided into two major categories: thinning
and shedding. When hair thins, the hair become
smaller and smaller in diameter, it miniaturizes, i.e. its
diameter reduces from 60 microns to less than that. Patients
with early thinning, retain the same number of hairs per square
inch as they did originally. However, as each hair gets progressively
smaller, a bald spot becomes more and more visible. Eventually
the hair becomes so miniaturized that it disappears, the hair
is then considered lost, and a hairless bald spot results.
Thinning is a slow process, and its unusual to see an
increased number of hairs in your sink or your hairbrush.
Thinning is what takes place in male pattern hair loss.
hair sheds, the scalp skin becomes visible because
non-miniaturized hairs have fallen out. Patients with hair
shedding will often see hair in their brush, on their pillow
case, and on the floor. The medical factors responsible for
hair shedding are quite different than those which cause hair
thinning. Shedding can occur in either anagen or telogen phase
and may be the result of fever, childbirth, or chemotherapy,
etc. Most times, a video microscopic examination is required
to differentiate between anagen shedding and telogen shedding.
When alopecia or hair loss takes
place, it may take three different configurations on the scalp
- diffuse, patterned, and spotty.
hair loss describes hair falling out equally over the
entire scalp. This type of hair loss is usually of the shedding
rather than thinning variety, and may be the result
of fever, childbirth, chemotherapy, hyperthyroidism, etc.
hair loss is characterized by a loss of hair on
the front and crown of the scalp, with no loss on the
back and sides. This is seen in common male balding
and in some women as well. Pattern
hair loss is a form of thinning rather than
It is slow and progressive. Rarely is the hair count of lost hairs greater than the average fifty per day. Hair loss usually begins in Zone 1 and progresses to 2, 3, 4 etc. Sometimes it begins in Zone 5. In both cases, it never involves Zone 8, the area from which hair transplant grafts are taken.
hair loss is a unique form of loss characterized by a
moth-eaten appearance of the scalp and it is typically a shedding
type of loss. Unlike diffuse and pattern losses. the
spotty hair loss occurs with a random, irregular configuration.
common cause of a spotty loss is alopecia areata, an immunologic
rejection of ones own hair. This disorder is more common
in children, will often correct
with no treatment at all, but may on rare occasions, progress
to be quite extensive. Typical alopecia areata usually responds
quite well to local injections of cortisone into the hairless
areas. The skin in the area of hair loss is normal in appearance.
hair is more resistant to alopecia areata than is dark hair.
If an individual with salt and pepper hair develops a case
of severe alopecia areata, his hair might be described as
turning gray overnight. Reason: the dark hairs
have fallen rapidly over a few days, and only the gray hairs
the area of spotty hair loss is associated with scaling of
the skin, the diagnosis is often ringworm or fungus infection.
Fungus infections of the scalp must be treated with a course
of anti-fungal pills. Other forms of spotty hair loss may
be scarring, congenital defects, discoid lupus erythematosis,
etc. Unlike alopecia areata, these are associated with changes
in skin as well.
loss, due to shedding, is one of the more predictable effects
of hormonal changes in pregnancy. Approximately 3 to 4 months
after delivery, more than 50% of mothers report a mild to
moderate hair fall called telogen effluvium. This often continues
for about six months, and then gradually slows and stops.
The lost hair then begins to re-grow at the normal rate of
one half inch per month. Unlike hair loss in men, it affects
the entire scalp and is not limited to the top of the head.
The hair loss of pregnancy does not progress to eventual baldness.
loss following delivery is due to the abnormal synchronization
of growing and resting phases in the hair growth cycle. The
average non-pregnant woman loses about 50 to 100 hairs a day.
In pregnancy, hormones influence the hair to stop falling.
A few months after childbirth, normal hair loss resumes, and
the loss that would have taken place over nine months, is
dramatically compressed into one or two months. The hair loss
of pregnancy is a normal phenomenon. Doctors have observed
that women, who stop birth control pills, have a similar hair
It is not unusual for hair loss to
follow a high fever -- usually about two to three months later.
The loss is a telogen shedding that eventually self corrects.
When a high fever persists, the synchronization between anagen
and telogen hairs becomes disrupted, and many hairs enter
the two to three month telogen phase. When anagen is re-established,
the telogen hairs are pushed out by the newly-forming anagen
hairs. The medical term for this phenomenon is telogen
When hair falls out as in typical
male pattern hair loss, (also called androgenetic alopecia
or balding) it is not a full-sized terminal
hair that falls. A process called miniaturization takes
place. The hairs go through shorter and shorter anagen
cycles. And with each cycle,
the diameter of the hair shaft becomes progressively smaller
the remaining hairs in the balding area become vellus
hairs and then so tiny, that they vanish. Regardless
of how much hair is lost on top, no significant miniaturization
will take place in the permanent horseshoe-shaped area
that remains. See
Zone 8 in map of scalp above. Male pattern baldness
does not progress to the likes of Yul Brenner or Michael
Jordan ...these individuals shave the remaining fringe
of hair on the back and sides.
lose hair in a pattern similar to men, it is cause for medical
evaluation. If significant hormonal imbalance has taken place,
the loss may be associated with irregular periods, inability
to become pre growth of new body hair. Most women with pattern
hair loss do not have a hormone imbalance. Many have a family
history of similar loss in their female relatives, and but most
are otherwise healthy individuals. Pattern hair loss in women
should be medically evaluated with hair density counts, distribution
analysis, and hormonal screening tests. The treatment may be
hormone therapy, topical minoxidil, or hair transplant surgery.
male pattern balding, female pattern balding is not associated
with recession of the frontal hair line