Female hair loss: what it is and how to recognise it

Female hair loss, also called female pattern hair loss or female androgenetic alopecia, is the most common cause of thin hair in women. It is not a "baldness" like men's: it rarely leaves areas with no hair. What happens is that, over years, the hairs on top of the head become progressively thinner and shorter, the parting widens and the scalp becomes more visible.

Because it is slow and silent, it is often mistaken for temporary hair loss, stress or "a lack of vitamins", and the diagnosis comes late. Recognising it early matters, because treatments work better at halting progression than at recovering lost hair.

What female hair loss is

Miniaturisation: the follicle shrinks

In female hair loss, the follicles do not die suddenly. Over several cycles, the growth phase (anagen) shortens and the follicle itself gradually becomes smaller. Each new hair grows slightly thinner and shorter than the last, until some follicles produce only a fine, almost transparent hair, similar to facial down. Between one cycle and the next, the follicle may also stay "empty" for longer (the kenogen phase). The result is less volume, even if the number of follicles stays the same for a long time.

Genetics and hormones

The cause is multifactorial and not yet fully understood. There is a clear genetic component: between 40% and 54% of affected women have a family history, on the mother's or father's side. Androgen hormones play a part, but less clearly than in men: most women with female hair loss have normal hormone levels, and the medicines that block the conversion of testosterone into dihydrotestosterone have less consistent results in women. That is why many specialists prefer the term "female pattern hair loss" to "androgenetic alopecia".

In some women there is, in fact, an excess of androgens, for example in polycystic ovary syndrome. In these cases, hair loss usually comes with other signs, such as acne, excess body hair or irregular periods.

How many women it affects

It is much more common than people think and increases with age. Two population studies give an idea:

Source: Gan and Sinclair, 2005; Norwood, 2001.

The differences between studies reflect different criteria and populations, but the message is the same: it is not rare, it can start early and it becomes more common after the menopause. For more on this stage, see Menopause and hair loss: what is known.

How to recognise it

Signs that women usually notice

• The parting is wider than before, especially at the front and on top. See Wider parting: when it is worth assessing.
• The ponytail is thinner: the hair tie goes round more times.
• The scalp shows more on top of the head, especially in strong light, from above or in photographs.
• The hair does not grow as long as before and the ends look thinner.
• Many short, fine hairs near the parting, which do not reach the length of the rest.

The front hairline, at the forehead, normally stays. Unlike in men, deep temple recession is rare. Daily shedding may be increased, but many women with female hair loss notice no shedding at all: they only notice that "there is less hair".

The patterns and the scales

Doctors use scales to classify severity and track progress:

• Ludwig scale (1977): three grades of diffuse thinning on top of the head, from mild to marked, with the front hairline preserved. It is the best known, but not very sensitive to small changes (Ludwig, 1977).
• Sinclair scale: five reference photographs of the central parting, from normal (grade 1) to the most advanced (grade 5). It is simple and useful for tracking progress.
• Olsen pattern (Christmas tree): the thinning is more pronounced at the front and narrows towards the back, forming a triangle with its base at the frontal hairline (Olsen, 1999).
• Male pattern (Hamilton-Norwood): temples and crown. It is rare in women and, when it appears, it justifies looking for excess androgens.

The pull test

At the consultation, the doctor may gently pull a small lock of hair. In female hair loss, more hairs than normal come out only on top; if they come out in all areas, telogen effluvium or another cause becomes more likely.

What can look like female hair loss and is not

Several conditions cause thin hair in women. Telling them apart is essential, because the treatment is different.

How the diagnosis is made

Clinical history

The doctor asks when it started, how it has progressed, whether there is hair loss or only less volume, whether there is a family history, what the menstrual cycles are like, whether there is acne or excess body hair, what medicines you take (including the pill and hormone therapy), what your diet is like and whether there were recent triggers.

Examination and trichoscopy

The diagnosis is essentially clinical. Trichoscopy, a magnified examination of the scalp, helps to confirm it and rule out other causes. The key sign is the variability in hair thickness: in female hair loss, thick and thin hairs coexist, in greater proportion at the front and top than at the back of the head. See Trichoscopy: the examination that shows the scalp.

Rakowska and colleagues (2009) proposed trichoscopic criteria that compare the frontal area with the occipital area:

• Major criteria: more than four yellow dots in four images of the frontal area; average hair thickness lower at the front than at the back; more than 10% of fine hairs (under 0.03 mm) at the front.
• Minor criteria: at the front, compared with the back, more follicular units with a single hair, more fine (vellus) hairs and more discolouration around the follicles.

Two major criteria, or one major and two minor, allow a diagnosis with high specificity (about 98%).

Blood tests

There is no single test that confirms female hair loss, but tests are useful for finding factors that make it worse or other causes: a full blood count and ferritin, thyroid function, vitamin D and, when there are signs of excess androgens (acne, body hair, irregular periods), a hormone work-up. See Blood tests for hair loss: what to ask for.

Biopsy

It is rarely needed. It is reserved for atypical cases or when a scarring alopecia is suspected.

Treatments with evidence and realistic expectations

Female hair loss is chronic and progressive: without treatment, it tends to advance slowly. The realistic aim is to halt progression and, in some women, to recover some volume. Results are only assessed after six to twelve months, and maintenance is needed to keep them. The plan is always individual and set at the consultation.

Topical minoxidil

It is the treatment with the most evidence and the only one specifically approved for female hair loss in Europe. The Cochrane review (van Zuuren et al., 2016) confirmed that it is more effective than placebo. In the first weeks there may be a temporary increase in shedding, a sign that the follicles are re-entering growth. The most common adverse effects are scalp irritation and increased facial hair. It should not be used in pregnancy or during breastfeeding.

Low-dose oral minoxidil

Used outside its approved indications (off-label), it has gained ground in recent years. In a randomised trial of 52 women, 1 mg a day had similar efficacy to 5% topical minoxidil after 24 weeks (Ramos et al., 2020). It can cause increased body hair, fluid retention and, rarely, changes in blood pressure or heart rhythm. It should only be taken with a prescription and under medical supervision.

Antiandrogens

Medicines such as spironolactone or certain contraceptive pills may be considered, especially when there are signs of excess androgens. The evidence comes from studies of moderate to low quality. They are used off-label for this indication, require effective contraception (because of risk to the foetus) and monitoring with blood tests.

Other treatments

• Platelet-rich plasma (PRP): studies suggest benefit, but with very different protocols and limited quality of evidence.
• Low-level laser: some trials have shown increased density; modest results.
• Correction of deficiencies: iron, vitamin D or thyroid, when abnormal, should be corrected. They do not treat female hair loss, but may reduce any associated hair loss.
• Camouflage: hair fibres, coloured scalp sprays, cuts and hairstyles with more volume. They are a legitimate aid, especially in the first months of treatment.
• Hair transplant: it may be an option in selected cases, with a stable donor area.

Be wary of products or clinics that promise to "cure" female hair loss or guarantee results.

When you should ask for an assessment

The earlier the diagnosis, the more hair there is to preserve. At Luxmed, the hair medicine consultation includes a detailed clinical history, examination of the scalp, trichoscopy with follow-up photographs and, when indicated, blood tests. The treatment plan is agreed at the consultation and followed up over time.

This article is for information purposes and does not replace a medical consultation. The results of any treatment vary from person to person.

Frequently asked questions