What causes hair loss
Most hair loss is not one condition. It is several, they look superficially alike, and they respond to completely different treatment. Surgery is only appropriate for some of them.
This page is educational. It is not a diagnosis, and pattern recognition from a photograph is not a substitute for examining a scalp under magnification.
Androgenetic alopecia
Pattern hair loss is a sensitivity, not a deficiency. Follicles on the top of the scalp are genetically susceptible to dihydrotestosterone, a derivative of testosterone. Exposure over years causes those follicles to miniaturise — each growth cycle produces a shorter, finer, less pigmented hair until the follicle stops producing a cosmetically useful hair at all.
The follicles on the back and sides of the head do not share that sensitivity. That single fact is what makes transplantation possible: hair moved from the resistant zone keeps its resistance in its new location. This is called donor dominance, and it is why transplanted hair is durable while the native hair around it can keep thinning.
It is also progressive. A transplant redistributes hair; it does not switch off the underlying process. Anyone planning surgery without also planning for continued native loss is planning for a result that ages badly.
Causes that are not pattern loss
If your loss is one of these rather than pattern baldness, a transplant is usually the wrong first move — and sometimes the wrong move entirely.
Telogen effluvium
A large share of follicles enter the shedding phase together, usually two to three months after a trigger — illness, surgery, major weight loss, childbirth, severe stress. Diffuse, alarming, and typically self-resolving once the trigger passes.
Traction alopecia
Sustained mechanical tension from tight braids, weaves, extensions or turbans. Reversible early. If tension continues long enough the follicle scars and the loss becomes permanent — at which point it can sometimes be treated surgically.
Alopecia areata
An autoimmune condition producing discrete, smooth, round patches. Unpredictable, can regrow spontaneously, and is a reason not to operate — transplanted grafts can be attacked in the same way.
Scarring (cicatricial) alopecias
A group of inflammatory conditions that destroy the follicle and replace it with fibrous tissue. Requires diagnosis and medical control. Surgery into active inflammation fails.
Nutritional and endocrine
Iron deficiency, thyroid disease and some medications all cause hair shedding. These are worth excluding with bloodwork, because correcting them is far simpler than operating.
Mechanical and traumatic
Burns, scalp trauma, and scarring from previous surgery. These are often genuinely good surgical candidates, because the surrounding follicles are healthy.
The cause decides the plan
A clinic that quotes you a graft count before establishing what is actually causing your loss is guessing. Placing grafts into an active scarring alopecia wastes donor hair permanently. Operating during a telogen effluvium treats a condition that would have recovered on its own.
Examination under magnification, a history, and where appropriate bloodwork come first. Sometimes the honest outcome of that conversation is that surgery is not indicated, or not yet.
Questions
Sources: American Academy of Dermatology · ISHRS Consumer Advocacy
Related
Find out which one you are dealing with.
The assessment takes about two minutes and tells you whether an examination is the sensible next step.