HealthInfo Canterbury
Overview of polycystic ovary syndrome (PCOS)
Polycystic ovary syndrome (PCOS) is a condition that affects the way your ovaries work. It's common, affecting 5 to 10% of women.
When you have PCOS you have:
- high levels of the male-type hormone called androgen. Your ovaries usually make androgen, but in PCOS they make too much
- bigger than normal ovaries
- changes to your ovulation. In PCOS your ovary's follicles (small fluid-filled sacs that surround the eggs) fail to release eggs regularly from your ovaries (ovulate).
Despite the name you can have lots of cysts on your ovaries without having PCOS. You can also have PCOS without any cysts on your ovaries.
Causes of PCOS
We don't fully understand what causes PCOS, but it seems to involve a mix of factors.
- Your genetics may be a factor. PCOS tends to run in families.
- Your body might make too much insulin, a hormone that controls the level of glucose (sugar) in our blood. If your body isn't very sensitive to insulin (insulin resistant) it has to make much more to keep your blood glucose normal. This makes your ovaries produce more male-type hormones. If you have PCOS you may also have a higher risk of diabetes and heart disease later in life, especially if you are overweight.
- It might be related to being overweight. Many women with PCOS weigh more than is healthy for them, which increases the amount of insulin produced, but slim women also get it.
Symptoms of PCOS
Signs and symptoms of PCOS usually start around the time of puberty through to your early 20s. The main symptoms include:
- irregular periods or no periods
- difficulty getting pregnant (infertility)
- acne
- excessive hair growth (hirsutism). Extra hair often grows on your top lip, chin, chest and in a line down from your tummy button (navel)
- thinning hair and hair loss.
Sometimes you can have PCOS with no symptoms.
Being overweight is common, but it's not caused by the PCOS. You might also have depression, anxiety or low self-esteem because of the physical symptoms of PCOS.
Diagnosing PCOS
Your GP will ask you about your symptoms, periods, and medical history. They may suggest some tests such as:
- blood tests to measure your hormone levels and check your lipids (cholesterol and other blood fats) and glucose levels
- an ultrasound examination of your ovaries to look for cysts.
To diagnose PCOS, your doctor will need to find two out of three of the following:
- irregular or no periods
- high levels of androgen
- polycystic ovaries on ultrasound.
HealthInfo recommends the following pages
- Monash University Australia – Ask PCOS
This downloadable booklet is easy to read and provides the best available information about polycystic ovary syndrome.
On the next page: Treating polycystic ovary syndrome (PCOS)
Written by the Department of Endocrinology, Christchurch Hospital. Adapted by HealthInfo clinical advisers. Last reviewed September 2021.
Review key: HIPCO-15994
