PCOS

Page last reviewed: 13/07/2011

Polycystic ovary syndrome (PCOS) is a condition in which women typically have a number of small cysts around the edge of their ovaries (polycystic ovaries). They also have one or more additional symptoms.

 Symptoms of PCOS include irregular or light periods, problems getting pregnant, weight gain, acne and excessive hair growth.

Women with PCOS either fail to ovulate (see box), or they ovulate infrequently, which is why it is one of the leading causes of fertility problems.

Polycystic ovaries

Polycystic ovaries are ovaries containing a large number of harmless cysts that are no bigger than 8mm each. Normal ovaries have only about half this number of cysts.

The cysts are egg-containing follicles that have not developed properly (see box) because of a hormone imbalance (see PCOS - causes).

Often in PCOS, none of these follicles develops enough to release an egg, meaning ovulation does not take place.

Also, in some women, levels of the hormone testosterone (or other male hormones) are higher than normal, which results in many of the typical symptoms.

Many women have polycystic ovaries without having the syndrome (without the symptoms). Some women have the syndrome, but have normal looking ovaries on ultrasound.

How common is it?

About one in five women has polycystic ovaries, and approximately one in 10 has PCOS to some degree.

Who is affected?

Many women with PCOS are overweight or obese, and have an acquired form of PCOS. They may have excessive body hair and hair loss from the head.

PCOS also tends to run in families. If you have PCOS but are not overweight, you probably have a history of PCOS in your family.

Women with PCOS may also have a family history of diabetes and high cholesterol.

Outlook

PCOS cannot be cured, but the symptoms can be treated. PCOS - treatment options include lifestyle advice (losing weight) and the combined contraceptive pill.

If polycystic ovary syndrome is not properly managed, it can lead to problems in later life, such as type 2 diabetes and high cholesterol levels.

Cyst
A cyst is a fluid-filled sac or cavity in the body.
Ovaries
Ovaries are the pair of reproductive organs that produce eggs and sex hormones in females.
Swelling
Inflammation is the body's response to infection, irritation or injury. It causes redness, swelling, pain and sometimes a feeling of heat in the affected area.
Testosterone
Testosterone is a male sex hormone that is involved in making sperm. It causes the development of male sexual characteristics, such as the voice getting deeper. Testosterone is also found in small amounts in women.
Ultrasound
Ultrasound scans are a way of producing pictures of the inside of the body using sound waves.
Uterus
The uterus (also sometimes known as the womb) is a hollow, pear-shaped organ in a woman where a baby grows during pregnancy.

Normal ovulation

During each menstrual cycle the ovaries release an egg (ovum) into the uterus. This process is called ovulation and usually occurs once a month.

Before the egg is ready to be released, it develops inside a tiny fluid-filled space (called a follicle) on the ovary. Each month several follicles start to develop, but in most cases only one matures fully and releases an egg.

The ovaries are also responsible for making oestrogen, the main female hormone, and small quantities of androgens (male hormones), such as testosterone.

Page last reviewed: 13/07/2011

The classic symptoms of polycystic ovary syndrome (PCOS) are:

  • irregular periods regular or
  • light periods, or no periods at all
  • problems getting pregnant (because of irregular ovulation or failure to ovulate)
  • weight gain
  • thinning hair and hair loss
  • acne
  • depression or mood changes
  • excessive hair growth (hirsutism)

However, not all women with PCOS have all of these symptoms, and each symptom can vary from mild to severe.

Symptoms usually become apparent in your late teens or early twenties. In many women, the only symptoms are menstrual problems or a failure to conceive.

Risks in later life

Cardiovascular disease

Having PCOS can lead to an increased risk of:

  • diabetes
  • high blood pressure
  • high blood cholesterol levels

These conditions can cause stroke or heart disease later in life. 

This increased risk is due to long-term resistance to insulin (a substance released by the pancreas to control blood sugar levels), obesity and hormone imbalances. See PCOS - causes for more information.

Endometrial cancer

Women who have had absent or irregular periods for many years have a higher-than-average risk of developing cancer of the womb lining (endometrial cancer).

However, the chance of getting endometrial cancer is still very rare, and certain treatments to regulate periods, such as the Pill,can minimise this risk.

Blood
Blood supplies oxygen to the body and removes carbon dioxide. It is pumped around the body by the heart.
Cholesterol
Cholesterol is a fatty substance made by the body that lives in blood and tissue. It is used to make bile acid, hormones and vitamin D.
Heart
The heart is a muscular organ that pumps blood around the body.
High blood pressure
Hypertension is when the pressure of the blood in your bloodstream is regularly above 140/90 mmHG.
Insulin
Insulin is a hormone released by the pancreas that helps the body to control blood sugar levels.
Obesity
Obesity is when a person has an abnormally high amount of body fat.
Womb
The uterus (also known as the womb) is a hollow, pear-shaped organ in a woman where a baby grows during pregnancy.

Page last reviewed: 13/07/2011

The exact cause of polycystic ovary syndrome (PCOS) is unknown, but the following factors often lead to its development.

Resistance to insulin

Insulin is a hormone produced by the pancreas to control the amount of sugar in the blood. It helps to move glucose out of the blood and into cells, where it is broken down to produce energy.

Insulin resistance means that the body's tissues are resistant to the effects of insulin. The body therefore has to produce extra insulin to compensate.

High levels of insulin cause the ovaries to produce too much testosterone (see below), which interferes with the development of the follicles and prevents normal ovulation.

Weight gain

Insulin resistance often makes you overweight, as raised insulin levels can lead to weight gain. Being overweight makes the symptoms of PCOS more pronounced because excess fat causes the body to produce more insulin. 

Hormone imbalance

Many women with PCOS are found to have an imbalance in certain hormones:

  • Raised levels of luteinising hormone (LH), which is created in the pituitary gland to stimulate ovulation and hormone production in the ovaries. This excess is thought to have an abnormal effect on the ovaries.
  • Raised levels of testosterone and other male sex hormones, which results in many of the symptoms of PCOS (all women produce testosterone, but normally in much lower levels than men).
  • Reduced levels of follicle-stimulating hormone (FSH) and progesterone.
  • A thyroid gland that does not function normally. The thyroid gland produces hormones that keep the metabolism functioning effectively. In PCOS, levels of these hormones may be lower than normal.
  • Raised levels of prolactin (only in some women with PCOS). This hormone usually stimulates the breast glands to produce milk in pregnancy.

It is not known what causes these hormone problems.

Insulin
Insulin is a hormone released by the pancreas that helps the body to control blood sugar levels.
Obesity
Obesity is when a person has an abnormally high amount of body fat.
Ovaries
Ovaries are the pair of reproductive organs that produce eggs and sex hormones in females.
Pituitary gland
The pituitary gland is a pea-sized gland in the centre of the head, which hangs below the brain and produces hormones.
Testosterone
Testosterone is a male sex hormone, which is involved in making sperm and sexual characteristics such as the voice getting deeper. Testosterone is also found in small amounts in women.
 

Page last reviewed: 13/07/2011

If you have any of the typical symptoms of polycystic ovary syndrome (PCOS), such as irregular periods and excess hair growth, see your GP. 

Your GP will base a diagnosis of PCOS on:

  • your symptoms
  • an ultrasound scan, which shows if you have polycystic ovaries (a chain of cysts is often seen, and the ovaries are enlarged)
  • blood tests, which establish the blood levels of:
    - hormones, such as luteinising hormone (LH) and testosterone
    - insulin levels
    - glucose (measured after a 10-hour fast)
    - cholesterol (measured after a 14-hour fast)

Your GP should also check your blood pressure.

Referral to a specialist

If your GP diagnoses you with PCOS, they may refer you to a specialist - either a gynaecologist (specialist in treating conditions of the female reproductive system) or an endocrinologist (specialist in treating hormone problems).

Your specialist will discuss with you the best way to manage your symptoms. They will advise you on any lifestyle changes to make, and start you on any necessary medication (see PCOS - treatment).

Follow-up

If you have been diagnosed with PCOS, you should request annual checks of your blood pressure, blood sugar and cholesterol readings to prevent the possible long-term effects of the condition.

Blood
Blood supplies oxygen to the body and removes carbon dioxide. It is pumped around the body by the heart.
Cholesterol
Cholesterol is a fatty substance made by the body that lives in blood and tissue. It is used to make bile acid, hormones and vitamin D.
Cysts
A cyst is a fluid-filled sac or cavity in the body.
Insulin
Insulin is a hormone released by the pancreas that helps the body to control blood sugar levels.
Ovaries
Ovaries are the pair of reproductive organs that produce eggs and sex hormones in females.
Testosterone
Testosterone is a male sex hormone, which is involved in making sperm and sexual characteristics such as the voice getting deeper. Testosterone is also found in small amounts in women.
Ultrasound
Ultrasound scans are a way of producing pictures of inside the body using sound waves.

Page last reviewed: 13/07/2011

Polycystic ovary syndrome (PCOS) cannot be cured, but the symptoms can be effectively treated.

Many of the symptoms can be managed through losing weight and adopting a healthy lifestyle (see below).

Other treatment options include:

  • hormone treatment
  • diabetes drugs
  • Vaniqa cream (eflornithine)
  • clomifene
  • surgery

Lifestyle changes

In overweight women, the symptoms of polycystic ovary syndrome (PCOS) can be greatly improved by losing excess weight (see box).

Losing weight will reduce the amount of insulin that your body needs to produce. This then reduces testosterone levels and improves the chances of ovulation. 

Menstrual and fertility problems will improve, along with a decrease in excessive hair growth and acne.

You can lose weight by following a suitable diet and doing 45-60 minutes of aerobic exercise every day. Your GP can refer you to a dietician, who will offer you advice. Weight loss of just 5% can lead to a significant improvement in PCOS.

Hormone treatment

Some anti-male hormone drugs can be used to block the 'masculine effects' (such as raised testosterone levels) of PCOS. These drugs include:

  • cyproterone acetate
  • spironolactone
  • flutamide
  • finasteride

Cyproterone acetate is the most effective drug for lowering testosterone levels, which will reduce growth of unwanted hair. However, there is no need to take this if you do not have raised levels of male sex hormones.

Hormone treatment can also control irregular or absent periods. The contraceptive pill or progestogen-only pill may be recommended to induce regular periods. This will also reduce your long-term risk of cancer of the endometrium if you do not have periods. 

Gonadotrophins (hormones produced by the body that stimulate the ovaries) may be recommended for some women with PCOS who have not responded to clomifene (see below). However, there is a risk that gonadotrophins may overstimulate the ovary and cause multiple pregnancy. An alternative to this treatment is surgery (see below).

Diabetes drugs

A diabetes drug called metformin can help increase ovulation in women with PCOS, along with other treatments. It may also reduce health risks from insulin resistance and the effect of abnormal levels of male hormones. It can be taken with clomifene (see below).

However, metformin is not a weight loss drug.

Pioglitazone and rosiglitazone are other diabetes drugs that may reduce insulin resistance and improve your menstrual cycle, and hence your fertility.

 

Vaniqa cream

Vaniqa cream blocks the action of an enzyme found in hair follicles that is needed for hair growth. The cream slows down the growth of unwanted facial hair, which may be a symptom of PCOS.

However, it does not remove hair or cure unwanted facial hair, so you may wish to use it alongside a hair-removal product.

Improvement may be seen as early as four to eight weeks after treatment.

Clomifene

If you are trying to conceive but not ovulating, your ovaries can be stimulated with a fertility drug called clomifene. 

Clomifene corrects your hormone imbalance and makes you more likely to ovulate, therefore improving your fertility.

Surgery

A minor surgical procedure called laparoscopic ovarian drilling (LOD) may be a treatment option.

Under general anaesthetic, your doctor will make a small cut in your lower abdomen and pass a long telescope called a laparoscope through into your abdomen. The ovaries are then surgically treated using heat or a laser.

The aim is to destroy the tissue that is producing androgens (male hormones).

LOD has been found to lower levels of testosterone and luteinising hormone (LH) and raise levels of follicle-stimulating hormone (FSH). This corrects your hormone imbalance and therefore restores the normal function of your ovaries.

The National Institute for Health and Clinical Excellence (NICE) recommends that women with PCOS who have not responded to clomifene should be offered LOD because it is as effective as gonadotrophin treatment (see above) and is not associated with multiple pregnancy.

Other medications

  • If you are overweight you may be prescribed a weight-loss drug, such as orlistat.
  • If you have high levels of cholesterol in your blood, you may be prescribed a statin (such as simvastatin).
  • You may also be offered treatment for acne.
Insulin
Insulin is a hormone released by the pancreas that helps the body to control blood sugar levels.
Ovaries
Ovaries are the pair of reproductive organs that produce eggs and sex hormones in females.
Testosterone
Testosterone is a male sex hormone, which is involved in making sperm and sexual characteristics such as the voice getting deeper. Testosterone is also found in small amounts in women.

Pregnancy risks

If you have PCOS, you have a higher risk of pregnancy complications, such as high blood pressure, pre-eclampsia, gestational diabetes and miscarriage.

Women with PCOS who are obese have a particularly high risk, especially if they also have high testosterone levels and body hair growth.

Losing weight before pregnancy (if you are obese), treating high luteinising hormone (LH) levels and treating insulin resistance will reduce the miscarriage risk.

Losing weight

A normal body mass index (BMI) is 19-25.

  • If you have PCOS and your BMI is more than 30, you be will be especially difficult to treat.
  • If you have PCOS and your BMI is more than 35, you are seriously at risk of medical problems.
  • If you have PCOS and your BMI is more than 40, the risk of medical problems is so high that pregnancy is inadvisable.

 

Content provided by NHS Choices www.nhs.uk and adapted for Ireland by the Health A-Z.

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