Associated risks for PCOS can include:

• Insulin resistance
• Weight gain / obesity
• Prediabetes / type 2 diabetes
• Cardiovascular disease
• Metabolic syndrome
• Endometrial cancer

Insulin resistance

Insulin resistance is a state where the body can't carry out the normal actions of insulin. One of the roles of insulin is to keep the levels of glucose in the blood stable. In PCOS high levels of insulin can increase the production of male hormones (androgens such as testosterone) in the ovaries. This contributes to symptoms such as menstrual irregularity, difficulty in ovulating and excessive hair growth and acne. Up to 80 per cent of women with PCOS have insulin resistance. Being overweight can contribute to insulin resistance.

Men and women without PCOS can also have insulin resistance through being overweight, not having a healthy diet or being physically inactive. Women with PCOS may have a specific type of insulin resistance that is different to the insulin resistance associated with obesity. Where a woman with PCOS gains weight, this can then further worsen insulin resistance and the signs of PCOS.

Weight gain and obesity

PCOS can occur in both slender and overweight women; however up to 75 per cent of women with PCOS are overweight or obese. This excess weight is more likely to be concentrated around the abdominal (stomach) region. This gives women with PCOS an 'apple' shape. Women without PCOS tend to be a 'pear' shape, with weight concentrated around the hips, buttocks and thighs.

Being overweight, and especially having a high amount of abdominal obesity, is associated with a higher risk of insulin resistance, which may lead to problems with fertility. Greater abdominal weight is also associated with a higher risk of type 2 diabetes and cardiovascular disease (including high blood pressure and heart disease) later in life.

A simple tool to assess if you are overweight or obese is the Body Mass Index or BMI. This is calculated as your weight (in kilograms) divided by your height (in metres) squared . 

For example, a woman who weighs 90 kg and is 167 cm tall, will have a BMI of:

A simple way to assess your amount of abdominal weight is measuring your waist circumference. To measure this accurately you should:

• Place a tape measure directly on your skin, or on no more than one layer of tight clothing horizontally halfway between your lowest rib and the top of your hipbone (roughly in line with your belly button)
• Breathe out normally and take the measure
• Make sure the tape is snug, without squeezing the skin

Waist circumference less than 80 cm = Recommended waist circumference.

Waist circumference: 80-88 cm = Increased risk of obesity associated diseases such as type 2 diabetes and cardiovascular disease.

Waist circumference greater than 88 cm = Substantially increased risk of obesity associated diseases such as type 2 diabetes and cardiovascular disease.

It is important to be aware that 'waist lost' is just as important as 'weight loss' in women with PCOS and that even losing 5-10 per cent of your original body weight can improve symptoms.

Prediabetes and type 2 diabetes

Compared to women without PCOS, women with PCOS have a much higher risk (up to four times higher) of developing pre-diabetes (impaired glucose tolerance) and type 2 diabetes. Women with PCOS are also more likely to develop diabetes in their 30s and 40s. This risk is further increased by being overweight or obese, insulin resistant, or by having a first degree relative (immediate family member) with diabetes.

Women with PCOS can also have a higher risk of having diabetes in pregnancy (gestational diabetes). While being overweight can worsen these risks, these risks appear to be increased in PCOS independent of the effect of obesity.

Cardiovascular disease (heart disease)

Women with PCOS have a range of risk factors for cardiovascular disease such as:

• High blood fats or cholesterol
• High levels of 'bad' cholesterol or low density lipoprotein cholesterol which worsens the risk of developing heart disease

• High levels of inflammatory proteins which can alter the function of blood vessels and increase insulin resistance

Women with PCOS also have a greater risk of high blood pressure and increased signs of early cardiovascular disease in the blood vessels. These risk factors can lead to cardiovascular disease and women with PCOS have a 2-fold increased risk of heart disease or stroke. While being overweight can worsen these risks, these risks appear to be increased in PCOS independent of the effect of obesity.

Metabolic syndrome

Women with PCOS also have a higher prevalence of ‘metabolic syndrome'. Metabolic syndrome is a condition where there is a cluster of diagnoses including impaired glucose tolerance, high blood pressure, abdominal obesity and high blood cholesterol. Together these factors are strongly associated with insulin resistance and an increased risk of developing type 2 diabetes and cardiovascular disease.

Endometrial cancer

When chronic anovulation (lack of eggs being released regularly) occurs, this leads to a lack of menstruation or shedding of the lining of the uterus (endometrium). The endometrium can thicken which can increase the risk of abnormal cells that, as a woman ages, can develop into cancerous cells. This risk can be greatly reduced with treatments such as the oral contraceptive pill, which can improve the regularity of the menstrual cycles and the shedding of the uterine lining during menstruation. Adequate physical activity and having a healthy body weight can also assist in normalising periods and reducing the risk endometrial cancer.

Content updated 25 August 2011