Androgenetic alopecia in women: why it's different and what options exist in Spain

Androgenetic alopecia in women, now more accurately called female pattern hair loss (FPHL), is the most common form of hair loss in women and the most common non-scarring alopecia: the hair gradually miniaturises and the growth phase shortens, so what you typically see is a wider parting and less density at the crown, not bald patches. In Spain, the only drug group with a verified indication in the AEMPS product information for this situation in women is topical minoxidil at 2% and 5%. The evidence behind it is the strongest available: the Cochrane review calculated a mean increase of 13.18 hairs per cm² compared with placebo.

Why we no longer say simply "androgenetic"

The classic term, androgenetic alopecia, assumes that androgens are the driving force behind the process. In women that assumption has been increasingly qualified, and the preferred terminology has shifted to female pattern hair loss (FPHL) precisely because there is uncertainty as to whether androgens are the only contributor. The same literature also distinguishes early-onset forms from late-onset or postmenopausal forms, which do not behave in the same way or raise the same questions in the consultation.

What is well described is the mechanism at follicle level: a progressive shortening of the growth phase and progressive follicular miniaturisation. The hair does not disappear all at once; it becomes finer, shorter and less pigmented until it barely provides coverage. The frontal hairline may or may not be preserved, and the psychological impact is documented as serious, something worth naming because many women come to the consultation having played the problem down for years.

How it is classified: Ludwig, Olsen and the masculinised pattern

The three classifications in use describe different patterns. The Ludwig scale (1977) defines three grades of progression with diffuse loss over the central area of the scalp. The Olsen pattern is the so-called "Christmas tree", with a widening parting that opens out towards the forehead. And there is a Hamilton-type pattern, with bitemporal recession, closer to the male form. In some women the thinning is diffuse and also involves the parietal and occipital areas, which makes it harder to fit into a single scale.

In a Thai hospital series of 519 women, the Ludwig subtype was the most prevalent (51.1%), followed by Olsen (32.9%) and Hamilton-Norwood (16%). That distribution has consequences: the Hamilton-Norwood subtype predicted early onset (OR 2.14; 95% CI 1.39–4.22) and polycystic ovary syndrome (OR 2.02; 95% CI 1.55–4.84) compared with the Ludwig pattern. It is not a diagnosis, but it is a signal that in a young woman with temporal recession it makes sense to look beyond the scalp.

How many women, and at what age

There is no verified prevalence figure specific to Spain, so we have to turn to series from abroad. In a British study of 424 women assessed with the Ludwig scale, prevalence was 6% in women under 50 and 38% in women aged 70 or over. In a US sample of 1,006 women, overall prevalence was 19%. The reasonable reading is that this is a phenomenon that increases a great deal with age and that in young women it is considerably less common than social media conversation suggests.

The figure that helps most to put things in perspective is hair density: the normal mean is around 293±61.3 hairs/cm² at the age of 35 and falls to 211±55.1 hairs/cm² at 70. In that same study, most women with FPHL had densities in the lower half of the normal range, with overlap between Ludwig grade I and the group with no loss. Translated: a density below the mean does not amount to disease, and the diagnosis is clinical, not a single isolated number.

Topical minoxidil: what the evidence says and what the AEMPS says

This is the option with the best backing in women. The Cochrane meta-analysis found that a greater proportion of women treated with minoxidil (121/488) reported a moderate increase in regrowth compared with placebo (64/476), with a relative risk of 1.86 (95% CI 1.42–2.43), and an increase of 13.28 hairs/cm² across seven studies (95% CI 10.89–15.68); in the update, with 8 studies and 1,242 participants, the mean difference was 13.18 hairs/cm² (95% CI 10.92–15.44). Cochrane itself notes that more than half of the studies were at high risk of bias, a caveat worth holding on to. The 2012 Br J Dermatol review brought together 22 trials and 2,349 participants, 10 of them on minoxidil, and a 2017 meta-analysis concluded that minoxidil is effective in women. A 2021 narrative review in the Cleveland Clinic Journal of Medicine describes it as first-line treatment in FPHL.

On concentrations, the trial by Lucky and colleagues (381 women, 48 weeks) showed that 5% was superior to placebo across the three primary endpoints; 2% beat placebo on hair count and investigator assessment, but not on the patient's own assessment; and 5% beat 2% on that patient assessment, at the cost of more pruritus, irritation and hypertrichosis. The Blume-Peytaví study (113 women, 24 weeks) found that 5% foam once daily was not inferior to 2% solution twice daily, with less local intolerance.

Several presentations are registered in Spain. Minoxidil Biorga 2% is indicated in alopecia, particularly in men with hair loss or in women with generalised thinning of the hair. The product information for the 5% formulation records stabilisation of hair loss in 4 out of 5 patients, with growth varying from person to person and observable after four months or more of regular use. Alopexy 5% is contraindicated in cases of hypersensitivity, scalp disorders and previous poor tolerance of the 2% formulation. Minoxidil Viñas 5% is listed as indicated in moderate androgenetic alopecia, and the ISDIN/Dinaxil 5% product includes a specific precaution section for women, with hand washing after application. There is also a monograph for an official preparation of minoxidil 2% solution in the AEMPS National Formulary (FN/2006/PO/039, amended in 2024). All of this is product information, not a regimen: who can use it, at what concentration and for how long is decided by a doctor after assessing the individual case. If you want the detail on cost, we break it down in the price comparison of topical and oral minoxidil in Spain.

The timeframes and what happens if you stop

The product information is clear on something that causes a great deal of frustration: the effect does not appear before four months. And if treatment is interrupted, growth may stop and the hair may return to its initial stage within three or four months. In other words, this is not a course of treatment you are discharged from, but a maintenance treatment for as long as it remains useful. Misplaced expectations are the number one cause of giving up. We have set out the month-by-month timeline of a hair treatment, including the initial shedding, so you know what is normal and what is not.

A useful figure for understanding why the topical form is considered safe: after application to the skin, an average of only 1.7% of the dose is absorbed (range 0.3%-4.5%), whereas absorption by the oral route is complete, and above 2.4-5.4 mg/day there could be a systemic effect. Curiously, the product information itself acknowledges that the exact mechanism of action of minoxidil is unknown, although it stimulates hair growth in androgenetic alopecia (ATC code D11AX01).

Low-dose oral minoxidil: off-label in Spain

This needs saying before any figures: the Spanish product information for minoxidil covers cutaneous use only, so low-dose oral minoxidil is off-label use in Spain. That said, it is used and it has been studied. In a multicentre series of 1,404 patients, the most frequent indication was androgenetic alopecia (82.4%), followed by telogen effluvium (4.8%), alopecia areata (3.8%), frontal fibrosing alopecia (2.8%), lichen planopilaris (2.5%) and fibrosing alopecia in a pattern distribution (1.8%).

A randomised trial of 100 patients compared oral with topical: photographic improvement of at least one grade in 67% with oral and 73% with topical (p=0.652), with no statistically significant difference, but with hypertrichosis considerably more frequent in the oral group (30% versus 9%, p=0.011). Important: that study was not powered to demonstrate non-inferiority, so it does not allow us to conclude that the two routes are equivalent. If you are interested in the tolerability profile, we go through it in our map of the real-world adverse effects of low-dose oral minoxidil.

What about finasteride, dutasteride and spironolactone

Here we would rather be honest than exhaustive. We have not been able to verify in a Spanish primary source the indication, the contraindications or the warnings for finasteride or dutasteride in women, nor the status of off-label use of spironolactone in Spain. For that reason we are not going to give you figures or comparisons between them: every number you read in this article is anchored to a source. What we can say is that these are decisions taken in the consultation, with a clinical history, blood tests where appropriate and a conversation about contraception and pregnancy, because the considerations there are far from minor. If you have come looking for how the mechanism works, we explain it for a general audience in the article on how finasteride works in hair loss and what results to expect.

Nor do our sources include verified systematic reviews on PRP, mesotherapy, microneedling or low-level laser therapy specifically in women, or verified thresholds for ferritin, vitamin D, thyroid function or zinc that would justify supplementation. As for what is sold over the counter in pharmacies, we go through the available evidence in our analysis of what does and does not work in hair supplements such as biotin or saw palmetto.

Not every type of hair loss is female pattern

Before assuming FPHL, other conditions need to be ruled out, because the approach changes completely. Sudden, diffuse shedding a few weeks after childbirth, surgery, an aggressive diet or an illness points more towards telogen effluvium, the sudden hair loss that usually reverses. Well-defined round patches are a different picture altogether, which we explain in the article on what alopecia areata is and how it differs from common hair loss. And a receding frontal hairline with loss of eyebrows, or shiny skin with no follicular openings, should make you think of a scarring alopecia, as we set out in the piece on the warning signs of frontal fibrosing alopecia. That distinction, scarring or non-scarring, is what determines whether the aim is to recover density or to halt irreversible loss.

What to take away and where to start

Female pattern hair loss is common, progressive and treatable, but it is not resolved with a shampoo or four weeks of patience: the real timeframes run to months and the benefit lasts as long as the treatment is maintained. What makes the difference is a correct diagnosis, because not all hair loss is the same, and follow-up that supports you through those first months when hardly anyone sees anything. At AiON we do exactly that: prior medical assessment, prescription where appropriate by a registered doctor and ongoing follow-up of hair loss treatment. You can check in a few minutes whether the treatment fits your case.