The most common cause of hair loss in women is Androgenetic Alopecia (AGA), which is also known as Female Pattern Hair Loss. This is a genetic disease that can be inherited on many genes, but it does not affect everyone who carries the genes. By menopause, 40% of all women will be affected in some way. It is identified as a gradual onset of diffuse hair loss.
The problem’s basis is the male hormone found in all women. It attaches to sites on the hair follicles and affects the follicles that are genetically susceptible. These follicles have a shortening of the growth phase, and the hair from these follicles are short and thinner than normal ones.
Again, hair loss in women is generally diffuse, and there is usually a preservation of the frontal hairline. This is distinct from Male Pattern Hair Loss, with frontal peak and top loss. AGA’s onset is usually gradual with no specific bare areas. There does not appear to be an increase in shedding because the hair growth does not become less but is only affected.
At the medical exam, the scalp should be examined for redness, signs of infection, and scarring. A family history should be taken to look for a similar condition in other family members. Usually, there is not an endocrine cause for this problem, but if general hirsutism accompanies the finding, then a full hormonal investigation should be started.
The only FDA-approved treatment is the topically applied vasodilator called Minoxidil (Rogaine). It comes in an over-the-counter preparation of 2% and 5% foam or liquid, which are all effective. There seems to be better results with the 5%, but there may be an increased chance of local irritation. How it specifically works is uncertain but there seems to be an increased growth phase, and the hairs grow longer and stronger. Remember, the treatment is 2x per day and forever. When you stop, the hair you gained will be lost. Lastly, you may not see any results for 3-4 months, so patience is needed.
-Dr. P
http://www.forhair.com/The_Causes_of_Hair_Loss_.htm