Polycystic ovary syndrome (PCOS): What you need to know
Polycystic ovary syndrome (PCOS) is a common condition that affects how a woman’s ovaries work.
The 3 main features of PCOS are:
- irregular periods – which means your ovaries do not regularly release eggs (ovulation)
- excess androgen – high levels of “male” hormones in your body, which may cause physical signs such as excess facial or body hair
- polycystic ovaries – your ovaries become enlarged and contain many fluid-filled sacs (follicles) that surround the eggs (but despite the name, you do not actually have cysts if you have PCOS)
If you have at least 2 of these features, you may be diagnosed with PCOS.
Polycystic ovaries
Polycystic ovaries contain many harmless follicles up to 8mm (approximately 0.3in) in size.
The follicles are underdeveloped sacs in which eggs develop. In PCOS, these sacs are often unable to release an egg, so ovulation does not occur.
It’s difficult to know exactly how many women have PCOS, but it’s thought to be very common, affecting about 1 in every 10 women in western countries.
More than half of these women do not have any symptoms.
Symptoms of polycystic ovary syndrome (PCOS)
If you have signs and symptoms of PCOS, they’ll usually become apparent during your late teens or early 20s.
They can include:
- irregular periods or no periods at all
- difficulty getting pregnant as a result of irregular ovulation or no ovulation
- excessive hair growth (hirsutism) – usually on the face, chest, back, or buttocks
- weight gain
- thinning hair and hair loss from the head
- oily skin or acne
PCOS is also associated with an increased risk of developing health problems in later life, such as type 2 diabetes and high cholesterol levels.
What causes polycystic ovary syndrome (PCOS)?
The exact cause of PCOS is unknown, but it often runs in families.
It’s related to abnormal hormone levels in the body, including high insulin levels.
Insulin is a hormone that controls sugar levels in the body.
Many women with PCOS are resistant to the action of insulin in their bodies and produce higher insulin levels to overcome this.
This contributes to the increased production and activity of hormones like testosterone.
Being overweight or obese also increases the amount of insulin your body produces.
Treating polycystic ovary syndrome (PCOS)
There’s no cure for PCOS, but the symptoms can be treated. Speak to a doctor if you think you may have the condition.
If you have PCOS and are overweight, losing weight and eating a healthy, balanced diet can improve some symptoms.
Medicines can also treat symptoms such as excessive hair growth, irregular periods, and fertility problems.
A simple surgical procedure called laparoscopic ovarian drilling (LOD) may be recommended if fertility medicines are ineffective.
This involves using heat or a laser to destroy the tissue in the ovaries that’s producing androgens, such as testosterone.
With treatment, most women with PCOS can get pregnant.
Symptoms
If you experience polycystic ovary syndrome (PCOS) symptoms, they’ll usually become apparent in your late teens or early 20s.
Not all women with PCOS will have all of the symptoms, and each symptom can vary from mild to severe.
Some women only experience menstrual problems or cannot conceive, or both.
Common symptoms of PCOS include:
- irregular periods or no periods at all
- difficulty getting pregnant (because of irregular ovulation or no ovulation)
- excessive hair growth (hirsutism) – usually on the face, chest, back, or buttocks
- weight gain
- thinning hair and hair loss from the head
- oily skin or acne
You should talk to your doctor if you have any of these symptoms and think you may have PCOS.
Fertility problems
PCOS is one of the most common causes of female infertility. Many women discover they have PCOS when they’re having difficulty getting pregnant.
During each menstrual cycle, the ovaries release an egg (ovum) into the uterus (womb). This process is called ovulation and usually occurs once a month.
But women with PCOS do not ovulate or ovulate infrequently, which means they have irregular or absent periods and find it difficult to get pregnant.
Risks in later life
Having PCOS can increase your chances of developing other health problems in later life.
For example, women with PCOS are at increased risk of developing:
- type 2 diabetes – a lifelong condition that causes a person’s blood sugar level to become too high
- depression and mood swings – because the symptoms of PCOS can affect your confidence and self-esteem
- high blood pressure and high cholesterol – which can lead to heart disease and stroke
- sleep apnoea – overweight women may also develop sleep apnoea, a condition that causes interrupted breathing during sleep
Women who have had absent or irregular periods (fewer than 3 or 4 periods a year) for many years have a higher-than-average risk of developing cancer of the womb lining (endometrial cancer).
But the chance of getting endometrial cancer is still small and can be minimized using treatments to regulate periods, such as the contraceptive pill or an intrauterine system (IUS).
Causes
The exact cause of polycystic ovary syndrome (PCOS) is unknown, but it’s thought to be related to abnormal hormone levels.
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 from the blood into cells, where it’s broken down to produce energy.
Insulin resistance means the body’s tissues are resistant to the effects of insulin.
The body, therefore, has to produce extra insulin to compensate.
High insulin levels cause the ovaries to produce too much testosterone, which interferes with the development of the follicles (the sacs in the ovaries where eggs develop) and prevents normal ovulation.
Insulin resistance can also lead to weight gain, which can worsen PCOS symptoms, as excess fat causes the body to produce even more insulin.
Hormone imbalance
Many women with PCOS are found to have an imbalance in certain hormones, including:
- raised levels of testosterone – a hormone often thought of as a male hormone, although all women usually produce small amounts of it
- raised levels of luteinizing hormone (LH) – this stimulates ovulation but may have an abnormal effect on the ovaries if levels are too high
- low levels of sex hormone-binding globulin (SHBG) – a protein in the blood that binds to testosterone and reduces its effect
- raised levels of prolactin (only in some women with PCOS) – a hormone that stimulates the breast glands to produce milk in pregnancy
The exact reason why these hormonal changes occur is not known.
It’s been suggested that the problem may start in the ovary itself, in other glands that produce these hormones, or in the part of the brain that controls their production.
The changes may also be caused by resistance to insulin.
Genetics
PCOS sometimes runs in families. If any relatives, such as your mother, sister, or aunt, have PCOS, the risk of you developing it is often increased.
This suggests a genetic link to PCOS may exist, although specific genes associated with the condition have not yet been identified.
Causes
See your doctor if you have any typical polycystic ovary syndrome (PCOS) symptoms.
Your doctor will ask about your symptoms to help rule out other possible causes and check your blood pressure.
They’ll also arrange for you to have several hormone tests to determine whether the excess hormone production is caused by PCOS or another hormone-related condition.
You may also need an ultrasound scan to show whether you have a high number of follicles in your ovaries (polycystic ovaries). The follicles are fluid-filled sacs in which eggs develop.
You may also need a blood test to measure your hormone levels and screen for diabetes or high cholesterol.
Diagnosis criteria
A diagnosis of PCOS can usually be made if other rare causes of the same symptoms have been ruled out and you meet at least 2 of the following 3 criteria:
- you have irregular periods or infrequent periods – this indicates that your ovaries do not regularly release eggs (ovulate)
- blood tests showing you have high levels of “male hormones”, such as testosterone (or sometimes just the signs of excess male hormones, even if the blood test is normal)
- scans showing you have polycystic ovaries
As only 2 of these need to be present to diagnose PCOS, you will not necessarily need to have an ultrasound scan before the condition can be confirmed.
Referral to a specialist
If you’re diagnosed with PCOS, you may be treated by your doctor or referred to a specialist, either a gynecologist (a specialist in treating conditions of the female reproductive system) or an endocrinologist (a specialist in treating hormone problems).
Your doctor or specialist will discuss the best way to manage your symptoms. They’ll recommend lifestyle changes and start you on any necessary medicine.
Follow-up
Depending on factors like your age and weight, you may be offered annual checks of your blood pressure and screening for diabetes if you’re diagnosed with PCOS.
Treatment
Polycystic ovary syndrome (PCOS) cannot be cured, but the symptoms can be managed.
Treatment options can vary because someone with PCOS may experience a range of symptoms or just 1.
The main treatment options are discussed in more detail below.
Lifestyle changes
In overweight women, the symptoms and overall risk of developing long-term health problems from PCOS can be greatly improved by losing excess weight.
Weight loss of just 5% can lead to a significant improvement in PCOS.
You can find out whether you’re healthy by calculating your body mass index (BMI), which measures your weight relative to your height.
A normal BMI is between 18.5 and 24.9. Use the BMI healthy weight calculator to work out whether your BMI is in the healthy range.
You can lose weight by exercising regularly and eating a balanced diet.
Your diet should include plenty of fruit and vegetables (at least 5 portions a day), whole foods (such as wholemeal bread, wholegrain cereals, and brown rice), lean meats, fish, and chicken.
Your doctor may be able to refer you to a dietitian if you need specific dietary advice.
Medicines
A number of medicines are available to treat different symptoms associated with PCOS.
Irregular or absent periods
The contraceptive pill may be recommended to induce regular periods, or periods may be induced using an intermittent course of progestogen tablets (usually given every 3 to 4 months, but can be given monthly).
This will also reduce the long-term risk of developing cancer of the womb lining (endometrial cancer) associated with not having regular periods.
Other hormonal methods of contraception, such as an intrauterine system (IUS), will also reduce this risk by keeping the womb lining thin, but they may not cause periods.
Fertility problems
A medicine called clomifene may be the first treatment recommended for women with PCOS who are trying to get pregnant.
Clomifene encourages the monthly release of an egg from the ovaries (ovulation).
If clomifene is unsuccessful in encouraging ovulation, another medicine called metformin may be recommended.
Metformin is often used to treat type 2 diabetes but can also lower insulin and blood sugar levels in women with PCOS.
As well as stimulating ovulation, encouraging regular monthly periods, and lowering the risk of miscarriage, metformin can also have other long-term health benefits, such as lowering high cholesterol levels and reducing the risk of heart disease.
Metformin is not licensed for treating PCOS in some countries. Still, because many women with PCOS have insulin resistance, it can be used “off-label” in certain circumstances to encourage fertility and control the symptoms of PCOS.
Possible side effects of metformin include nausea, vomiting, stomach pain, diarrhea, and loss of appetite.
As metformin can stimulate fertility, if you’re considering using it for PCOS and not trying to get pregnant, make sure you use suitable contraception if you’re sexually active.
Letrozole is sometimes used to stimulate ovulation instead of clomifene. This medicine can also be used for treating breast cancer.
The use of letrozole for fertility treatment is “off-label.” This means that the medicine’s manufacturer has not applied for a license for it to be used to treat PCOS.
In other words, although letrozole is licensed for treating breast cancer, it does not have a license for treating PCOS.
Doctors sometimes use an unlicensed medicine if they think it’s likely to be effective and the benefits of treatment outweigh any associated risks.
If you can’t get pregnant despite taking oral medicines, a different type of medicine called gonadotrophins may be recommended.
These are given by injection. There’s a higher risk that they may overstimulate your ovaries and lead to multiple pregnancies.
Unwanted hair growth and hair loss
The combined oral contraceptive pill is usually used to treat excessive hair growth (hirsutism) and hair loss (alopecia).
A cream called eflornithine can also be used to slow down the growth of unwanted facial hair.
This cream does not remove hair or cure unwanted facial hair so you may use it alongside a hair removal product.
Improvement may be seen 4 to 8 weeks after treatment with this medicine.
If you have unwanted hair growth, remove the excess hair using methods such as plucking, shaving, threading, creams, or laser removal.
Sometimes medicines called anti-androgens may also be offered for excessive hair growth, which may include
- cyproterone acetate
- spironolactone
- flutamide
- finasteride
These medicines are unsuitable if you are pregnant or trying to get pregnant.
For hair loss from the head, a minoxidil cream may be recommended for use on the scalp.
Minoxidil is not suitable if you are pregnant or trying to get pregnant.
Other symptoms
Medicines can also be used to treat some of the other problems associated with PCOS, including:
- weight-loss medicine, such as orlistat, if you’re overweight
- cholesterol-lowering medicine (statins) if you have high levels of cholesterol in your blood
- acne treatments
IVF treatment
If you have PCOS and medicines do not help you to get pregnant, you may be offered in vitro fertilization (IVF) treatment.
This involves eggs being collected from the ovaries and fertilized outside the womb. The fertilized egg or eggs are then placed back into the womb.
IVF treatment increases the chance of having twins or triplets if you have PCOS.
Surgery
A minor surgical procedure called laparoscopic ovarian drilling (LOD) may be a treatment option for fertility problems associated with PCOS that do not respond to medicine.
Under general anesthetic, your doctor will make a small cut in your lower tummy and pass a long, thin microscope called a laparoscope into your abdomen.
The ovaries will then be surgically treated using heat or a laser to destroy the tissue that’s producing androgens (male hormones).
LOD has been found to lower levels of testosterone and luteinizing hormone (LH) and raise follicle-stimulating hormone (FSH) levels.
This corrects your hormone imbalance and can restore the normal function of your ovaries.
Pregnancy risks
If you have PCOS, you have a higher risk of pregnancy complications, such as high blood pressure (hypertension), pre-eclampsia, gestational diabetes, and miscarriage.
These risks are particularly high if you’re obese.
If you’re overweight or obese, you can lower your risk by losing weight before trying for a baby.