Most hair transplant surgeons refer to hair loss in stages as defined by the Norwood classification published in 1975 by O’Tar Norwood. It is the most widely used classification for hair loss in men in the world. It defines two major patterns and several variations of hair loss.
In the standard Norwood pattern, two areas of hair loss—a bitemporal recession and thinning crown—gradually enlarge and coalesce until the entire front, top and crown (vertex) of the scalp are bald with natural angles.
Most hair loss follows a predictable pattern although variations occur frequently. The stages of hair loss displayed are useful in determining baldness in most men. The following charts have been helpful for doctors and patients in determining the extent of the hair loss in males.
This Map of the head shows the terminology hair loss doctors used to describe different regions of the head. Here, we plainly see the difference between the temple region, frontal, and mid-scalp anterior.
Stages of Hair Loss Norwood’s Classification
Type I Hair Loss
Minimal or no recession of the hairline. This is commonly viewed as a normal mature, male hairline.
Type II Hair Loss:
Mild temporal recession giving a triangular appearance which tends to be symmetrical (the same amount of hair loss on both sides).
Type IIA Hair Loss:
The entire anterior border of the hairline lies high on the forehead. No sparing of the mid-frontal region is noted except some sparse hairs.
Type III Hair Loss:
This represents the minimal extent of hair loss sufficient to be considered as baldness according to Norwood. Most type III scalps have deep symmetrical recession at the temples that are bare or only sparsely covered by hair.
Type IIIA Hair Loss:
The area of hair loss approaches the frontal half of the superior scalp.
Type III Vertex Hair Loss:
In this presentation, the hair loss is primarily from the vertex with limited recession of the frontotemporal hairline that does not exceed the degree of recession seen in type III.
Type IV Hair Loss:
The frontotemporal recession is more severe than in Type III. There is sparse hair or no hair over the vertex. The two areas of hair loss are separated by a band of moderately dense hair that extends across the top. This band connects with the fully haired fringe on the sides of the scalp. Type IV is distinguished from type III vertex in which the loss is primarily from the vertex.
Type IVA Hair Loss:
The area of hair loss now extends beyond the frontal half of the superior scalp.
Type V Hair Loss:
The vertex hair loss region is still separated from the frontotemporal region but it is less distinct. The band of hair across the crown is narrower and sparser. The vertex and frontotemporal regions of hair loss are bigger. Viewed from above, types V, VI, and VII are all characterized by surviving hair on the sides and back of the scalp forming a distinct horseshoe shape.
Type VA Hair Loss:
This type represents the most advanced degree of hair loss within the variant group. If the hair loss becomes more extensive, it cannot be differentiated from the normal types V and VI.
Type VI Hair Loss:
The bridge of hair that crossed the crown is now gone with only sparse hair remaining. The fronto-temporal and vertex regions are now joined together and the extent of hair loss is greater.
Type VII Hair Loss:
The most severe form of hair loss presents as extensive loss. A narrow band of hair in a horseshoe-shape survives on the sides and back of the scalp. This hair is usually not dense and may be quite fine. The hair is also sparse on the nape of the neck and in a semicircle over both ears.
See Also:
Intro to Hair Loss
Hair Loss, Self-Image, & Society
Hair Anatomy
How Hair Grows
How Hair is Lost
Hair Loss in Women
Traction Alopecia
Hair Loss in Men
Norwood Hair Loss Chart
Frontal Hair Loss
How to Stop Hair Loss