What is male pattern baldness?

Male pattern baldness is a common type of hair loss that affects at least half of all men at some point. It is often thought to be passed down from mothers to sons. However, male pattern baldness is actually inherited from both sides of the family.

General balding occurs over time as the hair follicles shrink. At first, the hair usually becomes shorter and finer, until eventually new hair doesn't grow back at all.

Women can also experience pattern hair loss; however, this is different to men.


On the average scalp, there are around 100,000 hairs that are constantly growing, resting and shedding. Hairs grow at about four tenths of an inch each month and stay on the head for between 3-5 years. The stages of hair growth are: anagen, where active hair growth occurs; catagen, a phase of transition, and; telogen, where the hair rests and eventually falls out.

During healthy shedding of hair, approximately 100 hairs are shed each day; healthy new hairs continue to grow in place of those that are lost and no difference in thickness is seen. However, baldness occurs when thick, healthy hairs are replaced by short, fine hairs that are shed faster than usual.

Biology of hair loss, cause of hair loss, follicles and hair loss.Hairs are constantly growing (anagen phase), resting (catagen phase) and shedding (telogen phase). 

Male pattern baldness is linked to a particular male sex hormone (androgen) called dihydrotestosterone (DHT). High levels of DHT affect the hair follicles, causing hairs to become thinner and grow for a shorter period. As individual follicles are affected at different times, balding occurs gradually.

Certain genes for male pattern baldness are also known to be passed on from parents to their children.


A chemical substance secreted in one part of an organism and transported to another part of that organism, where it has a specific effect.

Risk factors

Factors that increase the chances of developing male pattern baldness include:

  • Increasing age;
  • One or both parents with pattern baldness, and;
  • Sensitivity of hair follicles to dihydrotestosterone (DHT).

Signs and symptoms

As the name suggests, male pattern baldness occurs in a particular pattern. It usually starts with receding of the hair around the temples, followed by general thinning and balding on top of the scalp. In many cases, hair remains at the sides and back of the head.

patterns of male balding, male baldness, male hair loss.Visual appearance of male pattern baldness.  


The slight indentations on each side of the head in front of the ears, at equal level with the eyes.

Methods for diagnosis

Your doctor will most likely diagnose male pattern baldness by looking at your scalp and asking questions about your family history and rate of hair loss. A blood sample may be taken to confirm or rule out an underlying medical condition, such as an overactive thyroid gland (hyperthyroidism), low iron levels (anemia) or changes in male hormone levels.


A chemical substance secreted in one part of an organism and transported to another part of that organism, where it has a specific effect.


An essential mineral required by the body. Iron is part of a protein in the blood called hemoglobin, which carries oxygen around the body.

Types of treatment

If you are concerned about hair loss, a number of options aim to slow or hide hair loss, stimulate regrowth or replace damaged hair. Although there is no cure for male pattern baldness, the following options are available:

Self care

Your doctor may recommend a balanced diet containing plenty of protein, fruit and vegetables to help maintain the health and thickness of remaining hair. Avoiding harsh styling or vigorous brushing is usually also recommended.

Cosmetic options to hide the appearance of hair loss include a toupee, wig or hairpiece, or coloring the scalp to match existing hair.


The two most common medications for male pattern baldness are minoxidil or finasteride.

Available over the counter as a foam or liquid, minoxidil is applied directly to the scalp for a minimum of 12 months. Side effects can include skin irritation and unwanted hair growth on the face.

Finasteride is a prescription tablet that is taken daily over a course of two years or more. In rare cases, it can produce low sex drive and erectile problems as side effects.

Results vary from person to person. They work by slowing the rate of loss of existing hair, but are unable to stimulate hair regrowth once it is lost. Once treatment is discontinued, hair loss will generally continue at its initial rate.

Hair transplant surgery

During hair transplantation, a surgeon removes 'donor grafts' of hair from the back and sides of the scalp and transplants them to balding areas. Each graft contains one or more hairs still attached to a small patch of skin. Surgery can take up to several hours and may need to be repeated more than once.

In most cases, the transplanted hair falls out after surgery and then regrows over a period of 1-3 months. For this reason, improvements may only be seen with time. Sometimes though, transplanted hair may appear unnatural, not grow as expected, or not grow at all. Results vary depending on a number of factors, including the extent of hair loss and individual recovery.

As with most surgery, side effects of hair transplant surgery may include pain, scarring, swelling, bleeding, numbness or infection. Sedative and local anesthetic medications are administered to help prevent pain and discomfort during the surgery.

baldness treatment, surgery for baldness, hair transplant for hair loss.Hair transplant surgery. 


Entry into the body of microorganisms that can reproduce and cause disease.

Local anesthetic

A type of medication that, when administered to an area, creates a localized loss of sensation by blocking nerve activity.

Potential complications

Male pattern baldness can increase the risk of sunburn on the scalp. However, this can be avoided by wearing a hat and/or applying sunscreen with a high sun-protection factor (SPF) when outdoors.

As hair loss affects the appearance, widespread or early balding may lead to psychological issues such as embarrassment, social withdrawal, low self-esteem or depression.


An indication of the level of protection a sunscreen provides against ultraviolet A and B light when applied correctly.


Male pattern baldness is usually permanent. Treatment results vary from person to person, depending on the option chosen and amount of hair remaining. Generally though, medications tend to slow the progress of hair loss, rather than stimulate new growth.


As male pattern baldness is largely caused by genetic and hormonal factors, it is generally considered to be a natural part of ageing that cannot be prevented. However, eating a balanced diet and looking after the scalp may help to improve the thickness of remaining hair if the balding is not widespread.


Relating to hormones, which are chemicals secreted in one part of an organism and transported to another part of that organism, where they have a specific effect.


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  2. Androgenetic alopecia. (2014 July 7). Genetics Home Reference. Accessed 10 July 2014 from link here
  3. Causes of Balding. Baldness Cure | Patient.co.uk. Accessed 10 July 2014 from link here
  4. Female pattern hair loss. DermNet NZ. Accessed 10 July 2014 from link here
  5. Hair loss in men and women (androgenetic alopecia). Accessed 10 July 2014 from link here
  6. Male pattern baldness: MedlinePlus Medical Encyclopedia. Accessed 10 July 2014 from link here
  7. Male pattern hair loss (androgenetic alopecia balding). DermNet NZ. Accessed 10 July 2014 from link here

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