The Hamilton-Norwood scale (sometimes only referred to as “Norwood scale”) is the primary classification system used in the medical field to gauge the degree of male pattern baldness. This measurement scale was first introduced by James Hamilton in the 1950s and later revised and updated by O’Tar Norwood in the 1970s.
Men tend to lose their hair in a few common patterns over the development of many decades. The Hamilton-Norwood scale provides quick reference images that show distinct stages of balding. This is important for doctors to classify the stage of balding.
There are many other classification scales used by doctors, researchers, and hair transplant surgeons. Different classification scales include male and female, or only female, but Hamilton-Norwood is typically used by practitioners when discussing male pattern baldness.
It presents a reference point to diagnose the degree of baldness, consider treatment options, and measure the effectiveness of any treatment.
The Seven Stages of Hamilton-Norwood
The Hamilton-Norwood scale has seven steps. Each step marks the severity and pattern of hair loss.
Stage 1. There is a lack of bilateral recessions along the anterior border of the hairline in the frontoparietal regions. No notable hair loss or recession of the hairline.
Stage 2. There is a small recession of the hairline around the temples. Hair is also lost, or sparse, along the midfrontal border of the scalp, but the depth of the affected area is much less than in the frontoparietal regions. This is commonly referred to as an adult or mature hairline.
Stage 3. The first signs of significant balding appear. There is a deep, symmetrical recession at the temples that are only sparsely covered by hair.
Stage 3 vertex. The hairline stays at stage 2, although there is notable hair loss on the crown of the scalp (the vertex).
Stage 4. The hairline recession is harsher than in stage 2, and there is scattered hair or no hair on the vertex. There are deep frontotemporal recessions, usually symmetrical, and are either bare or very sparsely covered by hair.
Stage 5. The areas of hair loss are more significant than in stage 4. They are still divided, but the band of hair between them is thinner and sparser.
Stage 6. The connection of hair that crosses the crown is gone with only sparse hair remaining. The frontotemporal and vertex regions are joined together, and the extent of hair loss is more significant.
Stage 7. The most drastic stage of hair loss, only a band of hair, going around the sides of the head persists. This hair usually is not thick and might be dainty.
Norwood class A. This is a somewhat different and less common classification of hair loss. Norwood also defined a Type A variant from his standard classification system, which is distinguished by two major features and two minor features.
1) the border of the hairline grows to the rear without leaving an island of hair in the mid-frontal region
2) there is no synchronous development of a bald area on the vertex. Rather, the frontal hairline recession keeps progressing to the rear of the scalp.
1) there is sparse hair scattering in the area of hair loss
2) the horseshoe-shaped areas of hair that continue on the side and back of the scalp tend to be more extensive and touch higher on the head.
How is male pattern baldness diagnosed?
Common male pattern baldness is usually diagnosed based on the form and pattern of hair loss, along with a comprehensive medical history, including questions about the predominance of hair loss in your family.
How is hair loss treated?
Hair loss treatments are most potent when started early. It’s more manageable to slow down hair loss than it is to incite new hair growth. Hair follicles that stop creating hair become dormant after about two years and can’t be reactivated. However, there are ways to rejuvenate your hair follicles and start-up hair growth, such as Laser Hair Growth Helmets, and Pep Factor.
Laser Hair Growth Helmets. Low-level laser therapy is known as red light therapy and cold laser therapy, highlights, and empowers photons in the scalp tissues. These photons get absorbed by weak cells, which then encourages hair growth. At FACE, we use this type of treatment in our Laser Hair Growth Helmets.
Pep Factor. This serum is designed from the first drop with the intention of magnifying Fibroblast. Fibroblast Growth Factors (FGF) directs a range of various biological functions, including cellular proliferation, durability migration. FGF is also responsible for the renewal of tissue, including skin and hair follicles. UMA’s research laboratory has designed this unique formula.