The Norwood Scale, Class 1–7: Understanding Male Pattern Hair Loss
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Male pattern balding (androgenetic alopecia) can be many things – annoying, unsettling, discouraging – but one thing it’s not is unpredictable. As the name suggests, male pattern hair loss progresses in a predictable manner or pattern. It first shows up along the hairline, which may gradually take on an ‘M’ shape at the widow’s peak. Eventually, the mid-crown hair shortens and thins, until a bald patch emerges. At the most advanced stage, only a thin band of hair is left around the base of the scalp. In the 1950’s, this pattern was studied and categorized into 7 classes that came to be known as the Norwood Scale.
The Norwood Scale is a descriptive tool used to diagnose hair loss in men (the Ludwig Scale is used for women). In order to treat your hair loss effectively, your doctor must understand its severity and how its progressing, along with your age and family medical history. Read on to find out what Norwood Stage you’re at, and what options – including prescription hair loss medication, topicals, and hair transplant – are available to you.
What is the Norwood Scale?
The Norwood Scale (or Hamilton-Norwood Scale) is a classification system that quantifies and categorizes the stages of male-pattern baldness. It was created by Dr. James Hamilton in the 1950s, then further developed by Dr. O’Tar T. Norwood two decades later. This revised version remains the most used classification system for male hair loss today.
The scale itself measures the progression of hair loss. This means that higher numbers on the scale correspond with a higher degree of hair loss. While 1 represents no noticeable hair loss, 7 indicates near total hair loss, with only a horseshoe pattern of hair remaining around the sides of the head.
Male pattern baldness is caused by an excess of DHT (dihydrotestosterone), a male sex hormone related to testosterone. Many other factors contribute to hair loss. Your age, ethnicity, genes, and hair color will determine how much hair you might lose and if you are a good candidate for a hair transplant.
Hair Loss Stages According to the Norwood Scale
Norwood Class 1
Class 1 on the Norwood Scale represents the normal head of hair, no hair loss. It is considered an age appropriate hairline, normal maturation of that typically occurs from adolescence to adulthood. Thus, Norwood Class 1 is not considered balding.
It is possible, although unlikely, to remain at a Norwood 1 and never experience further hair loss. The best way to know if your hair loss is due to aging or early male pattern balding is to speak with a professional.
Norwood Class 2
Class 2 on the Norwood Scale marks the beginning of a receding hairline and the appearance of a more triangular “widow’s peak” on the forehead. Class 2 hair loss is still not considered balding according to the Norwood Scale.
This early phase may be unsettling to some––and more significant hair loss may follow. However, at this phase hair loss is highly treatable, making Class 2 the ideal time for intervention. Medications like finasteride and minoxidil inhibit DHT (the hormone responsible for hair loss) from binding to your follicles. These medications are proven to be very effective at halting hair loss and helping you keep the hair you have.
Is a hair transplant a viable option at this stage? Probably not, but only a qualified expert, like a Bosley physician, will be able to determine candidacy and need for the procedure at this phase.
Norwood Class 3
At Norwood 3, patients exhibit a more significant decline in hair above the temples and forehead, and the hairline starts to resemble an M, U, or V shape. Hair loss can also occur at the crown during this stage, which is known as a Class 3 vertex.
Hair loss at Class 3, and any class beyond it, is considered balding per the Norwood Scale. At this stage, hair transplant is a viable option, especially for those with a Stage 3 vertex who want to avoid hiding their balding spot.
It is important to consider the patient’s age, family history, and expectations during a hair transplant. Younger men may continue to lose hair around the forelock and temples, so it’s important that they continue a regimen of minoxidil or finasteride to prevent future hair loss from this area.
Norwood Class 4
Norwood Stage 4 is considered balding, and this is where hair loss typically becomes more noticeable on the crown. Patients may also have significant hair loss above the temples and the front anterior areas. A bridge of hair typically divides the crown (vertex) from the top of the head (mid-scalp).
A person with Norwood 4 hair loss can have excellent results from a hair transplant. A doctor can fill in the bald areas on the crown and temples, and the results can be maintained with medication. Bosley doctors have helped thousands of men at a Norwood 4 achieve a full, healthy head of hair.
Norwood Stage 5 hair loss tends to be quite noticeable, with most hair loss occurring on the frontal area and crown. The “bridge” between the crown (vertex) and top of your head (mid-scalp) begins to split, meaning the bald spots merge into one another. Transplanting at this stage of hair loss can yield great results.
Norwood Class 6
At Stage 6 of the Norwood Scale, the bridge has completely disappeared, leaving one large bald spot. Some hair typically remains around the sides of the head. Men at this point are still eligible for a hair transplant, but the results can be limited depending on how much donor hair they have left. Thus, the goal here is creating the most natural-looking head of hair with the donor hair that is available.
Norwood Class 7
Patients with Norwood Stage 7 hair loss show the most significant hair loss. Often, hair remains along the base of the head in a horseshoe-shaped band that wraps around the base of the scalp. There may still be sufficient donor hair for transplantation; however, the patient may have to decide what areas to focus on, as there may only be enough hair to cover the frontal area, crown, or mid-scalp.
Male pattern baldness isn’t a mystery. It affects millions of men, and progresses in a standard way, as defined by the Norwood scale. To summarize:
Norwood Stages 1-2 are not yet considered balding. If you’re worried about losing hair, oral and topical medications like finasteride and minoxidil are available, as well as natural supplements.
Norwood Stages 3-5 are when hair loss begins to become more noticeable. This is the optimal time for intervention, such as medication or hair transplant, or both.
Norwood Stages 6-7 are more advanced but patients can still experience great results with a hair transplant. The results will depend largely on how much hair the patient has left in their donor area.
Tracking the pattern of your hair loss can help to identify its cause. You can use your phone to periodically take pictures from the front, back, and top of your head, and compare them over the course of several months. If your hair loss takes on a different shape or progression, such as falling out in patches, it may be the result of a condition other than male pattern baldness. If your hair loss is sudden, or coupled with scaling, pain, or redness, you should speak to your doctor to determine the cause.
Regardless of where you’re at in your hair journey, Bosley can help. As one of the oldest and most trusted hair restoration practices, we’ve helped hundreds of thousands of men and women regain their hair and their confidence. Schedule a free consultation today to find out how we can help you!
What to do next?
To learn more about your hair restoration options and the average hair transplant timeline, The Complete Book on Hair Restoration, to see how great your hair can look. If you’re ready to do something about that bald spot or thinning hair now, schedule a FREE in-person or video consultation with a trained Bosley hair restoration specialist. Together with a Bosley Physician, we can help you find out what’s causing your balding and what treatment solution is right for you.