Excessive or abnormal hair loss is known as alopecia, and
there are several kinds. What all hair loss has in common, whether it's in men
or women, is a symptom of something that's gone wrong in your body. Your hair
will remain on your head where it belongs unless hormone imbalance, disease, or
some other condition occurs. That condition may be as simple as having a gene
that makes you susceptible to male or female pattern baldness or one of the
forms of alopecia areata, or it may be as complex as a whole host of diseases.
Fortunately, hair loss can be a symptom of a short-term
event such as stress, pregnancy, disease, or medication, which can all alter
hair's growth and shedding phases. In these situations, hair will grow back
when the event has passed. Once the cause of the loss is addressed, hairs go
back to their random pattern of growth and shedding, and your problem stops.
The first two types of hair loss in women are associated
with dihydrotestosterone (DHT), a derivative of the male hormone, testosterone.
Androgenetic Alopecia
The majority of women with androgenetic - also called
androgenic - alopecia have diffuse thinning on all areas of the scalp. (Men
rarely have diffuse thinning but instead have more distinct patterns of
baldness.) Some women have a combination of two pattern types.
Androgenic alopecia in women is due to the action of
androgens, male hormones that are typically present in only small amounts.
Androgenic alopecia can be caused by a variety of factors tied to the actions
of hormones, including some ovarian cysts, taking high androgen index birth
control pills, pregnancy, and menopause.
Just as in men, the hormone DHT appears to be at least
partially to blame for the miniaturization of hair follicles in women suffering
with female pattern baldness. Heredity plays a major factor in the disease.
Telogen Effluvium
When your body goes through something traumatic like child
birth, malnutrition, a severe infection, major surgery, or extreme stress, it
can impact your hair. Many of the 90% or so of hairs in the growing (anagen) or
transitional (catagen) phases can actually shift all at once into the resting
(telogen) phase.
About six weeks to three months after the stressful event,
the shedding phenomenon called telogen effluvium may begin. It is possible to
lose handfuls of hair at a time when in full-blown telogen effluvium.
For most who suffer with this, complete remission is
probable as long as severely stressful events can be avoided. For some women,
however, telogen effluvium is a mysterious chronic disorder and can persist for
months or even years without any true understanding of the triggering factors
or stressors.
Anagen Effluvium
Anagen effluvium occurs after any insult to the hair
follicle that impairs its cellular-level mitotic or metabolic activity. This
hair loss is commonly associated with chemotherapy. Since chemotherapy targets
rapidly dividing cancer cells, your body's other rapidly dividing cells -- such
as hair follicles in the growing (anagen) phase -- are also greatly affected.
Soon after chemotherapy begins, approximately 90% or more of hairs in the
anagen phase can fall out.
The characteristic finding in anagen effluvium is the
tapered fracture of the hair shafts. The hair shaft narrows as a result of
damage to the matrix. Eventually, the shaft fractures at the site of narrowing
and causes the loss of hair.
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