(Androgenic Alopecia, Alopecia Areata)
Hair Loss (Alopecia) Research in Portland, Oregon
Androgenic alopecia is a common hereditary hair thinning that occurs in both women and men. The difference between the genders is that women’s hair becomes diffusely thin and women do not become bald. In both men and women, hereditary thinning may begin in the teens, twenties, and thirties, and may continue to progress for decades.
How can I recognize androgenetic alopecia?
Typically, a young woman in her teens, twenties, or thirties gradually becomes aware that she has less hair on top of her head. She may notice her scalp become slightly visible, and it takes more effort to style her hair to mask the thinning. If her hair is long, she may notice that the ends are thinner and wispier and she cuts the hair shorter and shorter to maintain a fuller look. The size of her ponytail becomes smaller in diameter. While this is happening, she may also notice that her hair becomes greasy and stringy more quickly and she shampoos more often to keep the hair fluffy.
In most cases, the young woman does not notice increased hair shedding or a change in the amount of hair in her comb, brush or sink. However, in some women, their hereditary thinning is first unmasked by an episode of markedly increased hair shedding following childbirth, a high fever, or some other illness or stressor. Usually, this type of marked increase shedding runs its course over a period of months after the initiating factor is over, and is then followed by full hair re-growth. In a woman with genetic predisposition for hereditary thinning, she may not fully re-grow her hair following the shedding episode.
One of the earliest signs of androgenetic alopecia is a widening of the central part: the spacing between hairs increases. The thinning gradually becomes diffuse and may be present all over the scalp. But it is usually most pronounced over the top and sides of the head. There is much variation in the diameter and lengths of the hairs; some are thick and long and others are fine and short. This variation in hair size representation the gradual miniaturization of hair follicles, they become smaller and smaller. The hairline at the forehead is either straight or M-shaped. In most women, the M-shape hairline does not continue to recede as it may in some men. A few women, however, do show a fairly deep M-shaped recession.
What causes androgenetic alopecia?
This form of hair thinning is a normal hereditary trait that is caused by two factors; normal male hormone (testosterone) and hereditary. The influence of testosterone on genetically marked scalp hair follicle results in gradual miniaturization- with the smaller follicles producing hair that is fine and shorter. Over a period of time, this finer, shorter hair does not cover the scalp as well. At the same time, the miniaturization follicles are still present and the possibility to reverse the process and re-enlarge the follicles exists.
Women have a milder from of hereditary thinning than men – and do not become bald – because they have, much higher levels of female hormone (estrogens), which protect the hair follicle and lower levels of testosterone. It was recently discovered that scalp hair follicles in women can covert male hormone to female hormone and this adds further protection in women.
The genetic trait can be inherited from either mother’s or father’s side of the family or from both sides of the family. Affected members of the same family may have different degrees of hair thinning.
Hair thinning that appears for the first time in women of 50 years or older may not be due to the same hormonal process as in younger women. It may relate to the aging process or may be a combined effect of age and hormones.
How common is it?
Do women with androgenetic alopecia have too much male hormone?
Do I need any hormone tests?
What treatments are available?
Although there is no cure, there are several options for women with androgenetic alopecia. Female hormones (estrogens) help to slow thinning process and to keep the hair that is still present although they do not regrow or make hair thicker. Estrogens can be used in the form of an estrogen-dominate birth control pills (e.g. Desogen, Ortho-Cept, and Ortho Tri-Cyclen), or as estrogen replacement therapy (e.g. Premarin, Ogen, Estraderm patches in older women).
Topical minoxidil (Rogaine) is the first approved treatment for promoting hair growth. Although it is not very strong, its effect is real. Women whose scalps are visible may enjoy the improved coverage of the scalp by partially thicker and longer hairs. Topical minoxidil does not, however, completely reverse the thinning process or produce a thick head of hair. It must be applied twice daily for as long as a year in order to assess its effect. Treatment must be continued, otherwise normal heredity takes over and the newly stimulated growth is lost within one or two months. Side effects consist mainly of skin irritation in a small percent of users. Minoxidil (2% and 5%) are available over-the-counter. While minoxidil 5% is not yet FDA approved for women, it is safe and more effective than minoxidil 2%. Anti-androgens, such as spironolactone are selectively used.
Surgical treatment such as hair transplants are available. Hair transplants may be beneficial in redistributing hair from thicker areas to thin areas over the top of the scalp.
Women with substantial thinning may use smaller hair pieces or full wigs. They are safe, do not harm the hair, and do not accelerate the thinning process.
There is currently worldwide interest in hair research which will likely produce new treatments in the future. In the meantime, women can explore various cosmetic options. Much can be done with hair styling to cover a thinning scalp. The use of color, highlighting, perming, teasing, hair sprays, and mousse, creates the illusion of fullness. None of these cosmetic approaches are harmful to thinning hair if they are done carefully. Androgenetic alopecia is psychologically challenging. Medical and cosmetic options are currently available and research will provide still better treatments in the future.