Do I need any blood tests prior to a hair transplant?

The decision to order pre-operative blood tests depends on the hair transplant specialist. I recommend blood tests for CBC (complete blood count), PTT, INR (bleeding parameters) as well as Hepatitis B, Hepatitis C and HIV.   Patients with any previous heart problems may also be requested to obtain an electrocardiogram or “ECG.”

Is there a Minimum or Maximum Age for Hair Transplantation?

The minimum age for hair transplantation differs for each patient and depends on a number of factors. For patients with early onset androgenetic alopecia or with a family history of early onset or advanced androgenetic alopecia I may advise medical therapy first and delay a transplant until the mid 20s. This allows me to observe the rate of progression of hair loss over time. 

It is more challenging to predict the rate of hair loss in very young men with a family history of advanced hair loss. However, it becomes easier to predict the likely patterns of future loss by age 25-30.

There is no maximum age for men or women to have a transplant provided the patient is in good health.   

Do Androgens Cause Hair Loss?

It is well known that androgen hormones contribute to some types of hair loss.  The main culprit is the androgen hormone “DHT” or dihydrotestosterone, which is made from testosterone.  There are several pieces of evidence over the last few years that support the relationship between androgens and the development of androgenetic alopecia. This relationship is more direct in men than women.

First, it was appreciated even in ancient times that castrated young men do not go on to develop androgenetic alopecia, or male pattern balding.   Later it was understood that these men maintain low testosterone levels.  It was J.B. Hamilton in the 1940s who showed that wen testosterone was given back to castrated men later years, they developed male pattern balding.  Further evidence of the role of androgen hormones in hair loss came from study a group of men in the living in the Dominican Republic. Many of these men lacked the ability to convert testosterone to the potent androgen DHT.  Interestingly, these men did not develop male pattern baldness. Finally, we now have several medications available, such as finasteride and dutasteride, which block the ability of the body to covert testosterone to DHT. These medications can halt male pattern baldness in a significant proportion of men.

Most studies have shown that men with androgenetic alopecia have similar levels of blood testosterone compared to men who are not bald.  It appears therefore that men with androgenetic alopecia inherited hair follicles that are "more sensitive" to the effects of androgens rather than simply having higher levels of testosterone.

The relationship between androgens and hair loss is more complex in women. Androgens do play a role in the development of androgenetic alopecia, but likely not to the same degree as in men. Therefore, we now appreciated that the cause of androgenetic alopecia in women is much more complex.  It is for this reason that oral anti-androgen medications are helpful in treating hair loss in women, but do not have the same profound effects as in men.

Miniaturization: The Clue to the Early Diagnosis of Androgenetic Alopecia

One of the most common causes of hair thinning is androgenetic alopecia.  Men with androgenetic alopecia may notice hair loss at the top of the scalp as well progressive receding in the temples. Women with androgenetic alopecia notice thinning in the middle of the scalp.  The central hair part may become wider over time.  As hair thinning occurs the scalp becomes progressively more visible.   

I treat androgenetic alopecia with either 1) topical medications such minoxidil, 2) oral hormone blocking medications or 3) with hair transplantation. For some patients, I may recommend all three treatments. I encourage patients to consider using medical treatments in the early stages in order help maintain or improve the present hair density and prevent further loss over time.

Patients considering treatment for the very early stages of androgenetic alopecia often ask how I can absolutely sure they have androgenetic alopecia. Some of the doctors I teach ask the same question. How do you tell androgenetic alopecia is present if the patient does not actually have hair loss yet?What are the clues to the early diagnosis of androgenetic alopecia?

Androgenetic alopecia can be diagnosed based on the pattern of hair loss and by observing a process known as hair follicle “miniaturization.” When I lecture about androgenetic alopecia, I refer to miniaturization as the process by which hair follicles get skinnier over time.   It takes time for doctors to learn to identify hair follicle miniaturization, but I teach the following analogy to help others master this skill. 

Pretend that hair follicles are like tree trunks in the forest.  This analogy is kept in mind as the scalp is examined. If the size of the tree trunks is all the same – the patient does not have androgenetic alopecia.  If some of the tree trunks are fat and some of the tree trunks are skinny, the phenomenon of miniaturization is being observed. This is shown in the picture above. The most likely cause, by far, is androgenetic alopecia.

There are rarely other conditions that can be associated with miniaturized hairs besides androgenetic alopecia.  But this analogy is extremely important.  Many patients with concerns about hair loss end up receiving a diagnosis of androgenetic alopecia.  If there is no miniaturization, the diagnosis is wrong, and there is another reason for hair loss.

The Inheritance of Androgenetic Alopecia: Father’s Father ... Mother’s Father ... or Father’s Mother?

Androgenetic alopecia is common in the general population. In fact, the condition is often called “common balding”.  Approximately 50-60 % of men and 30-40 % of women will develop androgenetic alopecia by the age of 50.  

When I meet with patients, I generally ask about the hair characteristics of his or her mother and father.  I try to get a sense of his or her parent’s hair density and the age at which the parents started losing hair.   Although men and women with androgenetic alopecia often have a family history of androgenetic alopecia, it’s not absolutely necessary for the diagnosis.   In fact, a family history is least likely to be found in women diagnosed with androgenetic alopecia.  This is because the inheritance of androgenetic alopecia is much more complicated in women than in men.

There are many myths when it comes to hair loss and patients are often surprised to hear me say that the chance to inherit hair loss comes from both sides of the family tree.  Upon hearing this I commonly hear patients reply:

I thought hair loss came from the mother’s father?

or ... I thought hair loss came from the father’s mother?

or ... I thought hair loss came from the father’s father?

The main message is that hair loss is inherited from both mother and father and their respective sides of the family tree.  It’s possible for children to have high hair densities in adulthood even if dad has androgenetic alopecia.  Furthermore, it’s possible (albeit uncommon) for children to have significant androgenetic alopecia when dad or mom have minimal hair loss in adulthood.