Hair Loss Men
Most men experience at least some degree of hair loss in their lifetime, with the numbers increasing continuously with age. By their late 20’s, approximately 12% of men experience some

hair loss. By the time a man is in his 50s, he has a greater than 50% chance of displaying some genetic baldness.
The psychological effects of male hair loss vary greatly, with some people barely paying attention to their thinning hair and others being affected so severely that even a small amount of hair loss can limit their ability to feel comfortable in social situations and prevent their normal functioning at work. It is important that those who are having unusual difficulty dealing with their hair loss receive psychological support or counseling as well as medical treatment.
Fortunately, there are a number of excellent medical treatments that can prevent or postpone male hair loss when in its early stages and surgical hair restoration treatments that can restore a completely natural look, even if the hair loss has advanced. Over the past 10 years, treatments have improved dramatically, particularly with the introduction of the oral medication finasteride (Propecia) and the development of the surgical hair transplant procedures Follicular Unit Transplantation and Follicular Unit Extraction. Over the next decade we look forward for further progress towards the goal of cloning ones own hair, a technology in which significant progress has been made, but that is not yet available.
The Cause of Hair Loss in Men
By far the most common cause of hair loss in men is androgenetic alopecia, also referred to as “male pattern” or “common” baldness. It is caused by the effects of the male harmone dihydrotestosterone (DHT) on genetically susceptible scalp hair follicles. This sensitivity to DHT is present mainly in hair follicles that reside in the front, top, and crown of the scalp (rather than the back and sides) producing a characteristic and easily identifiable pattern described by Norwood.
DHT is formed by the action of the enzyme 5-alpha reductase on testosterone, the harmone that causes sex characteristics in men. DHT causes male hair loss by shortening the growth, or anagen, phase of the hair cycle, causing miniaturization (decreased size) of the follicles, and producing progressively shorter, finer hairs. Eventually these hairs totally disappear.
Norwood Classification
Norwood’s Classification of Male Pattern Alopecia
Class I >
represents an adolescent or juvenile hairline and is not actually balding. The adolescent hairline generally rests on the upper brow crease.
Class II indicates a progression to the adult or mature hairline that sits a finger's breath (1.5cm) above the upper brow crease, with some temporal recession. This also does not represent balding.
Class III is the earliest stage of male hair loss. It is characterized by a deepening temporal recession.
Class III Vertex represents early hair loss in the crown (vertex).
Class IV Is characterized by further frontal hair loss and enlargement of vertex, but there is still a solid band of hair across top separating front and vertex.
Class Vthe bald areas in the front and crown continue to enlarge and the bridge of hair separating the two areas begins to break down.
Class VI occurs when the connecting bridge of hair disappears leaving a single large bald area on the front and top of the scalp. The hair on the sides of the scalp remains relatively high.
Class VII patients have extensive hair loss with only a wreath of hair remaining in the back and sides of the scalp
Norwood Class A
Norwood’s Classification of Male Pattern Alopecia

The Norwood Class A patterns are characterized by a front to back progression of hair loss. Norwood Class A’s lack the connecting bridge across the top of the scalp and generally have more limited hair loss in the crown, even when advanced.
The Norwood Class A patterns are less common than the regular pattern (<10%), but are significant because of the fact that, since the hair loss is most dramatic in the front, the patients look very bald even when the hair loss is minimal. Men with Class A hair loss often seek surgical hair restoration early, as the frontal bald area is not generally responsive to medication and the dense donor area contrasts and accentuates the baldness on top. Fortunately, Class A patients are excellent candidates for hair transplantation.
The Diagnosis of Hair Loss in Men
The diagnosis of androgenetic alopecia in men is generally straightforward. It is made by observing a “patterned” distribution of hair loss and confirmed by observing the presence of miniaturized hair in the areas of thinning.
Miniaturization – the progressive decrease of the hair shaft’s diameter and length in response to androgens – can be observed using a densitometer, a hand-held instrument that magnifies a small area of the scalp where the hair has been clipped to about 1mm in length.
The diagnosis of androgenetic alopecia is supported by a family history of hair loss, although a positive history is not always identified. In older patients, their own history of passing through the different Norwood stages is strongly suggestive of male pattern alopecia.
If the hair loss is diffuse (thin all over) rather than following one of the specific Norwood patterns, the diagnosis can be more difficult. However, the presence of miniaturization in the areas of thinning usually confirms the diagnosis of androgenetic alopecia. If the diagnosis is still unclear, a number of other conditions must be ruled out.