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Overview of polycystic ovary syndrome (PCOS)

A diagram showing the difference between a polycystic and a healthy ovary 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:

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 do not fully understand what causes PCOS, but it seems to involve a mix of factors.

Symptoms of PCOS

Signs and symptoms of PCOS usually start around the time of puberty through to your early 20s. The main symptoms include:

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:

To diagnose PCOS, your doctor will need to find two out of three of the following:

  HealthInfo recommends the following pages

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.

See also:

Irregular periods

Overview of the female reproductive system

Page reference: 70671

Review key: HIPCO-15994