Female pattern baldness involves a typical pattern of loss of hair in women, caused by hormones, aging, and genes.

A hair grows from its follicle at an average rate of about 1/2 inch per month. Each hair grows for 2 to 6 years, then rests, and then falls out. A new hair soon begins growing in its place. At any time, about 85% of the hair is growing and 15% is resting.

Baldness occurs when hair falls out but new hair does not grow in its place. The cause of the failure to grow new hair in female pattern baldness is not well understood, but it is associated with genetic predisposition, aging, and levels of endocrine hormones (particularly androgens, the male sex hormones).

Changes in the levels of androgens can affect hair production. For example, after the hormonal changes of menopause, many women find that the hair on the head is thinned, while facial hair is coarser. Although new hair is not produced, follicles remain alive, suggesting the possibility of new hair growth.

Female pattern baldness is usually different from that of male pattern baldness. The hair thins all over the head, but the frontal hairline is maintained. There may be a moderate loss of hair on the crown, but this rarely progresses to total or near baldness as it may in men.

Hair loss can occur in women for reasons other than female pattern baldness, including the following:

• Temporary shedding of hair (telogen effluvium)
• Breaking of hair (from such things as styling treatments and twisting or pulling of hair)
• Patchy areas of total hair loss (alopecia areata -- an immune disorder causing temporary hair loss)
• Medications
• Certain skin diseases
• Hormonal abnormalities
• Iron deficiency
• Underactive thyroid
• Vitamin deficiency

• Thinning of hair over the entire head
• Hair loss at the crown or hairline, mild to moderate

Female pattern baldness is usually diagnosed based on the appearance and pattern of hair loss and by ruling out other causes of hair loss.

A skin biopsy or other procedures may be used to diagnose medical disorders that cause loss of hair.

Analysis of the hair itself is not accurate for diagnosing nutritional or similar causes of hair loss, although it may reveal substances such as arsenic or lead.

The hair loss of female pattern baldness is permanent. In most cases, it is mild to moderate. No treatment is required if the person is comfortable with her appearance.

The only drug or medication approved by the United States Food and Drug Administration (FDA) to treat female pattern baldness is minoxidil, used on the scalp. For women, the 2% concentration is recommended. Minoxidil may help hair to grow in 20% to 25% of the female population, and in the majority it may slow or stop the loss of hair. Treatment is expensive, however, and hair loss starts again when minoxidil use is stopped.

Hair transplants consist of removal of tiny plugs of hair from areas where the hair is continuing to grow and placing them in areas that are balding. This can cause minor scarring in the donor areas and carries a modest risk for skin infection. The procedure usually requires multiple transplantation sessions and may be expensive. Results, however, are often excellent and permanent.

The use of hair implants made of artificial fibers was banned by the FDA because of the high rate of infection.

Stitching (suturing) hair pieces to the scalp is not recommended. It can result in scars, infections, and abscess of the scalp.

Hair weaving, hairpieces, or change of hairstyle may disguise hair loss and improve cosmetic appearance. This is often the least expensive and safest method of dealing with female pattern baldness.

Female pattern baldness is of cosmetic importance only and does not indicate a medical disorder, but it may affect self-esteem or cause anxiety. The hair loss is usually permanent.

Complications are psychological stress and a loss of self-esteem due to change in appearance.

Call your health care provider if hair loss occurs and persists, especially if there is itching, skin irritation, or other symptoms. There might be a treatable medical cause for the loss of hair.

There is no known prevention for female pattern baldness.

Habif TP. Clinical Dermatology. 4th ed. St. Louis, Mo: Mosby, Inc. 2004:844.

Cummings CW, Flint PW, Haughey BH, et al. Otolaryngology: Head & Neck Surgery. 4th ed. St Louis, Mo; Mosby; 2005:677-679.