Female pattern hair loss (also known as female pattern androgenetic alopecia) represents a common condition with a multifactorial etiology that affects a large number of women worldwide. It is characterized by a progressive reduction in hair density, most notably on the crown and frontal scalp.
Initially, the condition was described by the general term “diffuse alopecia in women”. Nevertheless, when the role of male hormones in the classic pattern of male baldness was elucidated in the years after 1942, the term “androgenetic alopecia” was introduced to highlight the hormonal and genetic factors responsible for the development of the disease.
Hair loss and baldness in women is linked to substantial psychological morbidity due to the infringement of societal norms and gender identity issues. Albeit men perceive androgenetic alopecia as a stressful event that reduces their level of satisfaction with their body image, in general society tends to consider hair loss in men as normal and more or less expected because of the greater visibility of this phenomenon.
It is known that both the population frequency and the severity of female pattern hair loss increase with age. Two studies involving Caucasian women in the United States and the United Kingdom reported that the prevalence rates ranged from 3 to 6% in women under 30 years of age, increasing to 29-42% in women older than 70 years. The frequency of the disease is also lower in Oriental women.
Still, an adequate comparison between the prevalence of the condition in different societies is hindered by the lack of a universally agreed definition and, consequently, the deficiency of specific criteria for establishing the diagnosis. Depending on the sensitivity of the diagnostic procedure, the prevalence may vary significantly.
Generally speaking, female pattern hair loss starts during the reproductive years, though the pattern may be already noticeable at puberty in severe cases. A second peak of incidence is seen at menopause (usually between 50 and 60 years of age). However, the greatest need for treatment is felt among patients who are between 25 and 40 years of age.
There are several different classification schemes for female pattern hair loss. Among them, the Ludwig classification is the best accepted. It describes three unique stages that grades female hair loss according to its severity. This in turn helps both physicians and affected individuals to better understand the major factors in the diagnosis and treatment of female baldness.
In the first grade of Ludwig's classification, hair loss is mild, occurring chiefly on the top and front of the scalp. The second grade shows pronounced thinning of the hair on the crown, whereas the third grade is the most extreme. Here there is extensive hair loss and progressive thinning that usually results in full baldness.
In 1992, Savin developed nine computer images that are usually referred to today as the Savin scale. These illustrations demonstrate a refined visual gradient of hair loss. The scale thus represents a useful tool for assessing fine degrees of female baldness as it adds degrees of hair loss that are missing in the Ludwig classification system.
Finally, Sinclair's classification is a self-reported photographic measure of the patient’s own impressions of the severity of hair loss. It comprises five color photographs of a woman’s scalp, taken with the hair parted in the center. Women are required to select the photograph that they think most closely mirrors their own hair loss pattern. Consequently, this simple grading system can be used by both patients and physicians alike.