Hirsutism in women is the excess growth of dark and coarse hair over areas of the body where it ordinarily wouldn’t grow, such as the face and back. About one woman in 10 is affected.

Hirsutism is usually a symptom of an underlying problem rather than a medical condition in its own right. In most cases, the underlying problem is polycystic ovarian syndrome (PCOS), which is often associated with irregular menstrual cycles, acne, obesity, infertility and an increased risk of diabetes and osteoporosis. If you are concerned about the amount or distribution of body hair, see your doctor.

Hairiness is not the same as hirsutism

Tolerance to body hair is a cultural issue. A woman with more body hair than she would like should not assume she that has hirsutism.

Genetics play an important role in hair colour, thickness and distribution. For example, dark body hair and facial hair is common in women from many areas of the world including the Mediterranean, Middle East and the Indian subcontinent. Familial hirsutism (which means excess hair is inherited) is perfectly normal and is not associated with any underlying medical condition.

Male sex hormones and hirsutism in women

The female sex hormone oestrogen makes body hair fine and soft. Androgens are male sex hormones, including testosterone, which are responsible for masculine characteristics such as facial hair and coarse body hair. A woman’s ovaries and adrenal glands naturally make a small amount of androgens.

In most cases, hirsutism in women is thought to be caused by an abnormally high level of androgens. Other masculine features such as a deepened voice and increased muscle mass may also develop, and menstrual periods may cease (amenorrhoea). In other cases, women’s androgen levels are normal, but their hair follicles are overly sensitive to the effects of male sex hormones.

Some of the possible causes of hirsutism in women include:

• polycystic ovary syndrome (PCOS) – about nine in 10 women with hirsutism have PCOS
• androgen-secreting tumour – an abnormal growth on the ovary or the adrenal gland that produces androgens
• Cushing’s syndrome – the umbrella term for a collection of hormonal disorders characterised by high levels of the hormone cortisol
• adrenal hyperplasia – a group of disorders in which adrenal gland hormones (including androgens) are produced in the incorrect amounts
• hyperinsulinaemia – the overproduction of the hormone insulin, usually linked with diabetes
• hyperprolactinaemia – abnormally high levels of the hormone prolactin, which is normally associated with breastfeeding
• certain medications – for example, anabolic steroids cause unwanted hair growth as a side effect
• uncommonly, anorexia nervosa, hypothyroidism (under-active thyroid gland) and acromegaly.

The symptoms and signs of hirsutism depend on the underlying cause, but may include:

• a sudden change in hair colour, rate of growth, thickness or distribution
• excessive body hair in typically ‘male’ areas of the body such as the face, back, abdomen, inner thighs and buttocks.

Additional symptoms may include:

• hair loss on the scalp (‘male pattern baldness’)
• other skin conditions such as acne or seborrhoea
• development of warts within skin folds (acanthosis nigricans)
• unexplained increase in sex drive
• masculine characteristics such as deepened voice or increased muscle mass
• irregular or absent menstrual periods
• high levels of insulin
• infertility.

Hirsutism in women is diagnosed using a number of tests, which may include:

• medical history
• physical examination
• specific questioning – for example, about whether the onset of hairiness was gradual or sudden
• assessment of body hair using a standard scoring system
• blood tests to check testosterone levels
• thyroid function tests
• tests to check for PCOS – hormone tests and ultrasound scan of the ovaries
• tests to check for an androgen-secreting tumour – various scans.

Treatment and management will depend on the underlying cause. In addition to your usual doctor, you may need specialist doctors such as an endocrinologist (a doctor who specialises in hormone disorders) and a gynaecologist.

Treatment options may include:

• medications to block the effects of androgens
• anti-androgen medications to reduce your body’s ability to make androgens
• medications to help block the manufacture of androgens in the ovaries, such as the oral contraceptive pill
• insulin medications, if hyperinsulinaemia is present
• surgical removal of an adrenal or ovarian tumour
• for women who need contraception and help with menstrual cycle control, six month’s treatment with the oral contraceptive pill can significantly reduce excess hair growth.

Things you can do to look after yourself include:

• See your doctor if you think your medication is causing side effects. For example, some of the side effects of anti-androgen medication include weight gain, depression and fatigue. The doctor may alter your dose or prescribe a different medication.
• Medical treatments will not cause unwanted hair to drop out, so you will need to remove the hair using your preferred cosmetic method, such as waxing, depilatory creams, laser or electrolysis.
• You may want to try a prescription cream to inhibit hair growth. Keep in mind that the cream must be applied regularly and may take up to two months to show results. The cream doesn’t work for about two in three women.
• If PCOS is the underlying cause of hirsutism, losing weight may help because weight loss can naturally reduce the amount of androgens your body produces.
• During treatment, patience is important. It may take up to a year for noticeable results and as long as four years to achieve maximum results. See your doctor for more information.