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Sudden hair loss in women

Sudden hair loss in women
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Though hair loss can be distressing for both men and women, it is a natural part of the ageing process. Androgenetic alopecia, more commonly known as male- or female-pattern baldness, is thought to affect half of all men over the age of 50, and half of all women over the age of 65.

Male-pattern baldness is characterised by thinning on the crown and a receding hairline; in women, androgenetic alopecia causes widespread thinning on the head, but rarely a receding hairline. For both men and women, this kind of hair loss occurs gradually, slowly worsening over many years.

If you are a women experiencing the kind of hair loss described above (i.e. slow, gradual thinning of the hair on top of head) it’s likely that you have female pattern baldness.

If you are experiencing a different kind of hair loss, particularly hair loss that is patchy or has happened very suddenly, then it is unlikely that you have female-pattern baldness.

As hair loss can be associated with other health conditions, it’s a good idea to visit your doctor if you begin losing hair.

What causes sudden hair loss in women?

There are a number of different things that can cause sudden hair loss in women. One of the most obvious causes of sudden hair loss is medical treatment like chemotherapy, radiation or immunotherapy. These kinds of treatments frequently cause widespread, sudden hair loss (known as anagen effluvium) across the head and body.

Usually the hair loss is temporary and hair will grow back after the treatment has ended. If you are receiving a treatment like this, your doctor will inform of the risk of hair loss so it shouldn’t come as a surprise and shouldn’t be a cause for concern.

Other causes of sudden hair loss in women include alopecia areata, pregnancy, certain medications, intense stress and crash dieting. You can read more about these causes below.

Alopecia areata

Alopecia areata is thought to be caused by the immune system attacking the hair follicles and causing the hair to fall out. This type of hair loss leads to the sudden appearance of bald patches on the scalp. These bald patches can spread across the scalp and in severe cases can lead to total baldness on the head, and even across the body.

The sudden hair loss caused by alopecia areata can be alarming but in most cases, the hair loss is temporary. Hair should grow back on its own within a year; sometimes it will grow in fine and white, before returning to its normal colour and thickness.

Alopecia areata is more common in young people, and those who have autoimmune conditions such as hyperthyroidism. There is also thought to be a genetic factor involved, as one in five people who have alopecia areata have a family history of the condition.


During pregnancy many women find that their hair grows thicker. After giving birth it’s common to experience sudden and fairly significant hair loss. This is not a cause for alarm or a sign of permanent hair loss; the hair that you are losing is simply excess hair that built up during pregnancy.


If you go through a period of ill health, whether short or long-term, you may find that you experience some hair loss. Having a severe infection, receiving surgery, or cancer are all factors in hair loss. Hair loss caused by illness is known as telogen effluvium. It causes widespread thinning on the head and is usually temporary.


Certain types of medication such as anticoagulants and beta blockers can cause temporary thinning of the hair on the head. If the hair loss is noticeable and causing you distress, make an appointment to see your doctor.

Intense stress

Intense stress, whether physical or emotional, can cause the thinning of the hair on the head. Women can be more susceptible to this kind of hair loss after a difficult childbirth.

Crash dieting

Crash dieting can lead to telogen effluvium, the kind of thinning described above. Making sure that you eat a healthy, balanced diet that includes key nutrients is an important factor in maintaining healthy hair.

For more information on hair loss visit Alopecia UK.

I'm a woman experiencing sudden hair loss. Should I be worried?

Sudden hair loss can be alarming and if you do find yourself losing hair quickly you should visit your doctor.

Sudden patchy hair loss can be attributed to alopecia areata, which is normally temporary; noticeable thinning of the hair, meanwhile, is more likely to be related to illness, stress, hormonal changes, or lifestyle factors such as crash dieting.

Can dieting cause sudden hair loss?

Very restrictive short-term diets, or “crash diets” can lead to hair loss as they cause your body physical stress.

You may also experience some hair loss if you are consistently missing out on key nutrients associated with healthy hair growth. A diet deficient in iron, for instance, can cause anaemia, which is associated with hair loss. If you think your diet may be sufficient in key vitamins you should visit a doctor.

Does pregnancy cause sudden hair loss?

Yes and no. Some women may find that their hair temporarily thins after childbirth due to the emotional and physical stress of the experience. However, hair loss after pregnancy is also common because of excess hair growth during pregnancy. After your baby is born you may find that more hair than normal falls out, but this is usually just “excess” hair that has built up during pregnancy.

Hair loss associated with pregnancy and childbirth is usually temporary.


Image for illustrative purposes only. Posed by models.