Hair transplant: are you a good candidate? What to check first.

A hair transplant can give a natural, lasting result, but not for everyone and not at any time. This guide explains who makes a good candidate, what a proper pre-operative assessment includes and why medical treatment is part of the plan before and after surgery. That applies wherever you have it done, whether in Spain, the UK or further afield.

What a transplant can and cannot do

A hair transplant moves follicles from the donor area, usually the back and sides of the scalp, to areas where hair has been lost. Donor follicles are less sensitive to pattern hair loss and keep that trait after they are moved.

Two points are worth being clear about from the start:

• A transplant does not create new hair. It redistributes the hair you already have. The donor supply is limited and has to be managed with the future in mind.
• A transplant does not stop hair loss. It restores the area already lost, but your own hair around it is still exposed to the same cause.

So a good result depends as much on what happens before and after as on the surgery itself.

Who makes a good candidate

Clinical practice guidelines from the Indian dermatology association summarise the profile well ^[2]. A transplant can be considered in people with:

• Diagnosed pattern hair loss.
• A good-quality donor area.
• Good general health.
• Reasonable expectations of what can be achieved.

The same guidelines urge caution in these situations ^[2]:

• Very young people, whose hair loss is still evolving and whose final pattern is unknown.
• Extensive baldness, grades VI and VII on the Hamilton-Norwood scale, with poor donor density.
• Expectations the procedure cannot meet.
• Significant general health problems.

In women, hair loss is usually diffuse, across the crown and temples, rather than localised as in men. Before surgery, general contributing causes need to be looked for, and scarring or traction alopecia ruled out ^[3].

In scarring alopecia, a transplant is only considered once the condition has been inactive for some time. A systematic review of 123 patients found graft survival of 82.7% at 7 to 12 months, falling to 39.6% at 49 to 72 months, and 4 patients had their condition flare again ^[4].

In active alopecia areata or telogen effluvium, a transplant is not the answer: those conditions are treated differently.

What the pre-operative assessment includes

The consultation answers three questions: what is causing your hair loss, how much donor hair you have and whether your health allows surgery safely.

Diagnosing the cause

The most common cause is androgenetic alopecia ^[1]. It is confirmed through your history, an examination, standardised photographs and, where needed, trichoscopy. If the diagnosis is unclear, that is resolved before surgery is discussed. Our guide to how hair loss is diagnosed explains the process.

Assessing the donor area and the design

The density and thickness of the donor hair are assessed, along with the size of the area to cover. That shows whether the available hair is enough for your goal, now and in the future. The Indian guidelines recommend a minimum implanted density of 35 to 45 follicular units per square centimetre ^[2].

The hairline design should take account of your age and how your hair loss is likely to progress. A hairline that is too low or too dense in a young person can look out of place years later.

Pre-operative blood tests

Guidelines recommend, as a minimum, haemoglobin, a full blood count including platelets, clotting tests and a biochemistry profile that includes blood glucose ^[2]. In female pattern hair loss, anaemia and thyroid problems are also ruled out ^[2].

If your laboratory reports glucose in mmol/L, as in the UK and Scandinavia, and the Spanish lab in mg/dL, the conversion is straightforward: 5.6 mmol/L is about 100 mg/dL. Your doctor will interpret the figures either way.

Medicines and lifestyle

Your doctor will review everything you take, especially anticoagulants, antiplatelet medicines and supplements. A 2026 review identified smoking, diabetes and chronic sun damage as risk factors for complications ^[7]. Stopping smoking before surgery is one of the most useful things within your control.