Stages of Baldness

It is a common knowledge that baldness occurs in degrees and is a gradual phenomenon. Since it is not possible to convey the extent of baldness in words, a classification system was developed by Dr. Norwood. This is the most commonly used sytem today, although other more complicated systems are also available.

Broadly speaking, Norwood classification attempts to divide baldness in seven stages with stage I  being normal adult hairline and stage VII being total possible baldness. Although, there are many flaws in this system, it still gives a basic idea regarding the extent of baldness in an individual.

Stage I

Essentially normal adult male hairline (not to be confused with 'juvenile hairline'). Temporal recessions are well defined   with frontal hairline in normal position. No miniaturisation in crown region.

Stage II

The frontal hairline shows slight recession(< 2 cm), with more pronounced recession in
 temporal area.
The "A" variant implies that hair line is receding uniformly and that frontal forelock is
not spared. This means
exaggerated appearance of baldness and larger requirement of hair during transplant.

In this stage hair transplant should be done if the baldness is stable.
 Usually a single session is adequate.

Many surgeons defer operating in such patients, especially if they are young.

Stage III

This stage can be considered as watershed for transplant,
 because now the baldness is very obvious
and most transplant surgeons would consider performing a procedure in such patients.
 There is definite recession
in frontal hairline combined with deep temporal areas and usually thinned out
look in most of frontal area.
Crown may also show miniaturisation and/or actual hair loss (Stage III Vertex)

State IV

This is a more advanced state of baldness, in which frontal and
frontotemporal recession is deeper than in State III
and the density of hair in these areas is noticeably reduced.
 As the baldness moves from front to back,and circumferentially in crown area;
 a bridge of healthy hair remains in the mid section of scalp.
This area called the 'bridge' is characteristic of stage IV.
 Loss of bridge, is seen is considered a feature of
advanced baldness.

Stage V

Area of baldness keeps increasing and thinning of bridge segment is present.

Stage VI

In this stage there is total disappearance of the bridge segment that separates
 the two main areas of baldness.
The depth of the frontal and crown areas has expanded sideward and backwards.
In some individuals, frontal forelock may be spared to become 'isolated forelock'.

Stage VII

This is the most advanced stage of hair loss.
 In this stage only the universal safe zone remains.
Hair transplant is useful only in those individuals of stage VII who have good hair characteristics.

Hair transplant is possible from stage II through VII. Advanced stages of baldness usually require more than
one session to achieve maximum benefit.
In selected individuals mega sessions can be planned to cover large areas in one go.