The diagnosis of polycystic ovarian syndrome is based on the condition's symptoms, the discovery of multiple cysts using ultrasound scanning, and blood tests to establish the levels of hormones such as LH and testosterone. The cysts are two to eight millimetres in diameter. They often form a chain, described as the 'string of pearls' sign. The affected ovaries are enlarged.

In many cases of PCOS, the blood levels of male sex hormones (testosterone and androstenedione) are raised well above their normal low values. The insulin levels are also often raised.

If you have been diagnosed with polycystic ovarian syndrome, you should request regular (annual) checks of your blood pressure, blood sugars and cholesterol readings to prevent the possible long-term effects of the condition.