The Norwood scale (often referred to as the Hamilton-Norwood scale) is a popular visual system for measuring male pattern hair loss.
This condition affects more than half of UK men over the age of 50, and the Norwood scale uses simple pictures to chart its 7 stages. But the Norwood scale isn’t the only classification system available. Hair transplant surgeons and researchers may use an alternative reference to measure shedding, such as a scale that covers women only.
However, the Norwood scale is the most popular option for specialists when assessing a man’s pattern baldness. They can use it as a chart to accurately diagnose hair loss, inform patients about possible treatments, and evaluate how effective those treatments can be.
In this post, we’ll take a closer look at the Norwood scale, beginning with its 7 stages.
The 7 Stages of Hair Loss
The following stages measure the progression of pattern hair loss:
No visible signs of substantial hairline recession or thinning.
Mild recession occurs at the hairline, specifically at the temples. This is referred to as a mature hairline, and no further hair loss may occur (in some cases).
Clinically significant hair loss appears as recession at the left and right temple, creating one of three shapes — M, V, or U. Areas affected by recession will either be totally bald or show profound thinning.
The hairline remains at its stage 2 position while substantial hair loss affects the vertex (the crown).
The hairline recedes more noticeably than in stage 2, with little or no hair on top of the scalp. The patches of growth at the sides of the head are linked by a narrow band of hair.
Both areas of hair loss on either side of the band grow bigger, and the band itself becomes thinner.
Hair loss around the temples spreads to the bald vertex, and the band of hair on top of the scalp is at its thinnest or gone altogether.
Hair loss is at its most advanced. You may have hair at the back and sides of the head, but the top is bald.
If you develop Norwood Class A baldness, your hairline recedes directly back across the scalp: there’s no island of hair in the centre or bald spot at the vertex.
How Does Hair Loss Look on the Norwood Scale?
How Do Experts Diagnose Male Pattern Baldness?
Specialists will perform a physical examination and discuss your medical history to diagnose your hair loss.
While the majority of hair loss affecting men is diagnosed as male pattern baldness, a doctor will aim to eliminate other possible causes if:
- You’re below the average age for this condition to appear
- Your hair loss is unusual for any reason
Dermatologists or specialists in hair loss will examine your scalp carefully during a consultation. They’ll determine the pattern of the shedding, the level of hair loss so far, and may pull multiple strands away to check your follicles. It’s likely they’ll use the Norwood scale to discuss their findings with you.
The most successful hair loss treatments usually begin early on in the process. It’s more difficult to encourage new growth than to reduce the rate of shedding, as follicles that no longer produce strands grow dormant after a couple of years. And, sadly, they can’t be restarted.
That’s why surgery is the best form of treatment if you experience substantial hair loss.
Here are some of the most common over-the-counter options available:
Minoxidil is a topical treatment applied to the scalp, under the Rogaine brand. This is designed to prevent hairs from becoming thinner and promote new growth. Minoxidil may be used alongside alternative treatments.
You can try a variety of combs and more high-tech devices incorporating laser light. They may be built to encourage growth, but there’s no clinical proof that they’re effective (at the time of writing).
A doctor might recommend that you try finasteride (sold as Propecia or Proscar), based on how severe your baldness is and your previous response to over-the-counter treatments.
Finasteride is a pill, but’s unavailable on the NHS: you must order it privately in the UK. The standard dose is 1mg per day, according to the NHS.
You can try multiple procedures to treat your hair loss:
Hair transplantation involves transferring healthy follicles from one or more areas of the scalp to those affected by thinning/baldness.
Devices that stretch the skin are fitted beneath the scalp for around one month.
A technician applies tiny tattoos to the scalp to suggest that you have healthy hair growth across the scalp, but have shaved your hair.
A surgeon removes part of the scalp to bring areas with healthy hair growth closer. This may be used alongside a hair transplant.
What Triggers Pattern Hair Loss in Men?
Hormones, genetics, and environmental factors can all lead to male pattern baldness.
The genes you inherit from your mother and father affect how sensitive you are to androgens (a type of hormone), specifically dihydrotestosterone (DHT).
Every individual hair starts in a follicle and takes from 2 to 6 years to grow. It then transitions to the resting stage of the hair growth cycle before shedding. The cycle restarts when that follicle begins work on a new strand.
But follicles can start to shrink and the cycle can become shorter, due to a rise in androgens. DHT typically triggers miniaturisation, and causes strands to become finer and shorter over time. Follicles can get too small for new hairs to form, eventually leading to baldness.
Prevention and treatment complement each other, but as men lose their hair at different ages and at various speeds, it’s down to the individual to choose when they should take action to address hair loss.
Hair transplants are increasingly popular due to their affordability and effectiveness. You can undergo transplantations outside the UK at incredibly competitive rates.
A specialist can measure the state of your male pattern hair loss with the Norwood scale, and determine what they can do to treat you. A transplantation will be the best option if you want lasting, natural hair growth.
The Hamilton-Norwood scale is a visual tool used to identify different degrees of male pattern baldness, numbered from 1 to 7. Doctors and hair restoration specialists often use the Hamilton-Norwood scale to assess baldness, though its reliability is questionable due to differing conclusions.
A mature male’s normal hairline starts between 2.4 and 3.2 inches above the eyebrows, and has a clear U-shape. Men may also have a natural widow’s peak, though that’s fairly uncommon.
Type I has minimal or no hairline recession. With Type II, recession occurs at the frontotemporal areas of the hairline, typically in symmetrical patterns. Type III is the minimal level of hair loss to be recognised as baldness on the Hamilton-Norwood scale.
A Norwood 2 hairline may be caused by a maturing hairline, but it could indicate that further hair loss and thinning will occur in the future. However, patients can take steps to prevent additional hair loss and reverse it, even lowering the hairline to its original position.