How many hair transplants can a patient have?

Hair transplants: how many can a patient have?

The number of hair follicles available to move from the back of the scalp (the 'donor area') to the front or top of the scalp (the 'recipient area') is limited.  Someday, hair research may allow us to expand the number of hairs available, but for now there is a limited number. The number of grafts available to move depends on a number of factors, espeically how bald a person is destined to become.  It is generally estimated that between 4,000-10,000 follicular units are available in men. Men who are destined to have advanced balding patterns have less hair available to move than men destined to have minimal balding.

New study from Mount Sinai

A new research study by Dr Walter Unger and colleagues from the Department of Dermatology at Mount Sinai School of Medicine set out to refine these estimates even further. A group of 39 hair transplant surgeons were asked to estimate the number of 'permanent' follicular units available for surgery in a hypothetical 30 year old man destined to develop advanced balding (i.e. Hamilton Norwood Scale V or VI)

What were the results of the survey?

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Respondents indicated that men destined to have Hamilton Norwood Stage V balding had between 5,000 - 8,000 follicular units available for surgery and men destined to have Hamilton Norwood Stage VI balding had between 4,000 - 6,600 follicular units available for hair transplant surgery.Man with 4000 follicular units max in lifetime

Why are these results important?

This study reminds hair transplant surgeons (and patients) that there are a finite number of follicular units available for surgery. A middle aged man destined to have advanced balding in his  lifetime has two (and maybe three) surgeries maximum in their lifetime.   It is exteremely important to discuss with patients how grafts will be placed so that the appearance of bald areas of the scalp can be minimized throughout life.


Unger WP, Unger RH, Wesley CK. Estimating the number of lifetime follicular units: A survey and comments of experienced hair tranpslant surgeons. Dermatol Surg 2013;

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Dr. Jeff Donovan is a Canadian and US board certified dermatologist specializing exclusively in hair loss. To schedule a consultation, please call the Whistler office at 604.283.1887

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