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Polycystic Ovarian Syndrome (PCOS)

Polycystic Ovarian Syndrome (PCOS) - What it is

What is PCOS?
PCOS is a common condition affecting 10% to 13% of women of reproductive age. It is linked with hormonal imbalances that can affect your periods, fertility and your long-term health.

What is the difference between polycystic ovaries (PCO) and PCOS?
The term PCO describes the appearance of the ovaries seen on ultrasound. These ovaries are slightly larger than normal ovaries and have twice the number of follicles (fluid-filled spaces within the ovary that release the eggs when you ovulate). About 20% of women in the general population have ovaries with this appearance. Having PCO does not necessarily mean that you have PCOS. Women with PCOS have symptoms and may have PCO.

What are the symptoms of PCOS?
The symptoms of PCOS include:

  • Irregular and often infrequent menstrual 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, abdomen, back, upper thighs or buttocks
  • Weight gain
  • Thinning of hair or male-pattern baldness
  • Oily skin or acne
  • Depression and psychological problems can also result from having PCOS

What causes PCOS?
The exact cause of PCOS is unknown, but it often runs in families. If any of your relatives (mother, aunts, sisters) are affected with PCOS, your risk of developing PCOS may be increased.

It is thought that PCOS is related to abnormal hormone levels:

  • Insulin resistance
    Insulin is a hormone produced by the pancreas to control the amount of glucose (a type of sugar) in the blood. If you have PCOS, your body may not respond to insulin (insulin resistance), so the level of glucose is higher in your blood. The body therefore produces extra insulin to compensate. A high level of insulin can lead to weight gain, irregular menstrual periods, and cause the ovaries to produce too much testosterone. • 
  • Raised level of testosterone
    Testosterone, often thought as a male hormone, is also produced in small amounts by the ovaries in all women. Women with PCOS have slightly higher than normal levels of testosterone, which interferes with the development of the follicles and prevents normal ovulation. A raised level of testosterone is also associated with many of the PCOS symptoms mentioned earlier.

How is PCOS diagnosed?
Your doctor will ask about your symptoms, perform a physical examination, and arrange for some tests (blood tests and ultrasound scan) to help rule out other possible causes of your symptoms.

Women with PCOS often have symptoms that come and go, particularly if their weight goes up and down. This can make it a difficult condition to diagnose, which means it may take a while to get a diagnosis.

A diagnosis of PCOS can usually be made if other causes of the same symptoms have been ruled out and you meet at least two of the following three criteria:

  • Irregular, infrequent menstrual periods or no periods at all
  • Increase in facial or body hair and/or blood tests showing high testosterone levels
  • Ultrasound scan showing PCO

How can PCOS affect my long-term health?
Women with PCOS have been shown to have increased chance of developing a number of medical conditions later in life, as below:

One or two in every 10 women with PCOS go on to develop diabetes at some point in their lives. The risk is further increased if you are overweight, developed diabetes in pregnancy (gestational diabetes) and have relatives with diabetes. You should therefore have your blood sugar level checked regularly, every one to two years.

High blood pressure
Women with PCOS tend to have high blood pressure and this can lead to heart problems later in life. Screening for high blood cholesterol should also be performed regularly and managed accordingly to reduce the risk of developing heart problems.

Endometrial Hyperplasia and Cancer
If you have fewer than three to four menstrual periods per year, the lining of the womb (endometrium) can thicken (endometrial hyperplasia) and this may lead to endometrial cancer in some women. Treating these women with progestogen tablets every three months, taking oral contraceptive pills or using the intrauterine contraceptive system (MIRENA®) may reduce the chance of developing these conditions. PCOS does not increase your chance of developing breast or ovarian cancer.

Snoring and daytime fatigue
Women with PCOS who are overweight are at higher risk of having obstructive sleep apnoea (OSA). This is a condition where the walls of the throat relax and narrow during sleep, interrupting normal breathing. Women who snore loudly at night and feel very tired during the day may be referred for further assessment.

Depression and mood changes
The symptoms of PCOS may affect how you see yourself and how you think others see you. It can lower your self-esteem.

Pregnancy Risks
If you have PCOS, you have a higher risk of pregnancy complications, such as high blood pressure (hypertension), pre-eclampsia, gestational diabetes (GDM) and miscarriage. These risks are particularly high if you are also obese. If you are overweight or obese, you can lower your risk by losing weight before trying for a baby.

How is PCOS treated?
There is no cure for PCOS. However, a variety of treatments are available to address the problems of PCOS. Treatments are based on the symptoms you are having and whether you want to conceive or need contraception.

Weight loss and maintaining a healthy lifestyle
Many women with PCOS successfully manage their symptoms and long-term health risks without any medical intervention. Losing weight will help to regular insulin levels and help to restore ovulation and menstrual cycles. This is achievable by eating a healthy diet, exercising regularly and maintaining a healthy lifestyle.

If you need help with losing weight, speak to your doctor to consider being referred to a dietitian, taking medication or going for bariatric surgery.

Control of irregular menstrual periods
Periods can be regulated with the use of combined contraceptive (birth control) pills or induced with a course of progestogen tablets (given every two to three months). The menstrual cycle may become abnormal again when the pills are stopped. This will reduce the risk of developing endometrial hyperplasia and cancer.

Treatment of unwanted hair growth and hair loss
The birth control pill is often prescribed to treat excessive hair growth and hair loss. Medication can also be combined with cosmetic measures such as bleaching and electrolysis to lighten dark hair or remove the unwanted hair. You may also want to remove the excess hair by using methods such as plucking, shaving, threading, creams, or laser removal. All treatments should be taken for a few months before an improvement can be expected.

Some medicines called the anti-androgens (e.g., cyproterone acetate, spinorolactone, flutamide, finasteride) may also be offered for excessive hair growth and minoxidil cream for hair loss. These medicines are not suitable if you are pregnant or trying to get pregnant.

Treatment of fertility-related problems
Exercise and reduction of body fat can result in the resumption of ovulation. Weight loss of just 5% is shown to increase the number of ovulatory cycles and fertility in a high proportion of women with PCOS.

Medication such as letrozole, clomiphene citrate (Clomid®), metformin, injections of gonadotropins (hormone injections) and a surgical procedure called ovarian drilling may help to stimulate ovulation and increase your chances of getting pregnant. Speak to your doctor for further information. Some women may need further treatment such as in-vitro fertilisation (IVF) if all the above medication failed.

Teede HJ, Tay CT, Laven JJE, Dokras A, Moran LJ, Piltonen TT, Costello MF, Boivin J, Redman LM, Boyle JA, Norman RJ, Mousa A, Joham AE; International PCOS Network. Recommendations From the 2023 International Evidence-based Guideline for the Assessment and Management of Polycystic Ovary Syndrome. J Clin Endocrinol Metab. 2023 Aug 15:dgad463. doi: 10.1210/clinem/dgad463. Epub ahead of print. PMID: 37580314.

The information above is also available for download in pdf format.

Polycystic Ovarian Syndrome (PCOS) - Symptoms

Polycystic Ovarian Syndrome (PCOS) - How to prevent?

Polycystic Ovarian Syndrome (PCOS) - Causes and Risk Factors

Polycystic Ovarian Syndrome (PCOS) - Diagnosis

Polycystic Ovarian Syndrome (PCOS) - Treatments

Polycystic Ovarian Syndrome (PCOS) - Preparing for surgery

Polycystic Ovarian Syndrome (PCOS) - Post-surgery care

Polycystic Ovarian Syndrome (PCOS) - Other Information

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