Polycystic ovary syndrome (PCOS) is the most common female reproductive disorder, affecting around 10% of women. PCOS is partly diagnosed by measuring levels of male hormones (androgens), such as testosterone, in the blood. However, we should really consider PCOS a metabolic disorder with reproductive consequences, because for around 75-80% of women with PCOS the disorder is actually caused by the metabolic imbalance insulin resistance.
PCOS is in fact a body wide condition characterised by a variety of imbalances that can negatively impact overall health alongside fertility and chances of getting pregnant. Testing for key markers of these imbalances is an important first step in addressing PCOS, helping to ensure appropriate dietary and lifestyle changes can be made to improve reproductive health and chances of conceiving.
Hormonal imbalances and insulin in PCOS – what is the relationship?
PCOS is often talked about as a reproductive disorder, and it is true that it significantly impacts upon reproductive hormone balance and the ovaries. Women with PCOS produce higher levels of testosterone than normal, which contributes to a number of the physical symptoms of PCOS such as acne and excess hair. However, it is important to understand that these elevations in testosterone are actually caused by insulin resistance, a metabolic imbalance which leads to increased insulin levels. These high insulin levels signal the ovaries to produce testosterone, and also promote other hormonal imbalances seen in PCOS.
Insulin is a hormone that controls the body’s metabolism of glucose for energy. After we eat, insulin signals our cells to take glucose out of the bloodstream into the cells to be converted into energy. Women with PCOS are more likely to be resistant to this action of insulin and, as a result, they will have higher than normal levels of glucose and insulin circulating in their bloodstream. It is this elevation in insulin that is the root cause of the reproductive hormone imbalances seen in women with PCOS.
The measurement of free testosterone (the free androgen index FAI) is particularly relevant in PCOS as the elevation of insulin causes levels of testosterone to rise and also leads to a drop in levels of something called Sex Hormone Binding Globulin (SHBG). SHBG is a carrier molecule that controls the amount of hormones that are free and active in the body, so women with PCOS not only have higher levels of testosterone, but because of the corresponding drop in SHBG, this testosterone is even more active.
Insulin, Follicle Stimulating Hormone and Luteinising Hormone
Elevated insulin levels also impact the balance of luteinising hormone (LH) and follicle stimulating hormone (FSH) in women with PCOS, causing elevations in LH and a drop in FSH. Elevated LH further promotes testosterone production as LH signals the ovaries to produce testosterone, and low FSH inhibits proper ovulation leading to the absent or irregular periods often experienced by women with PCOS. The inhibition of proper ovulation causes immature follicles to accumulate in the ovaries and the development of the polycystic ovaries that are typical of the syndrome.
The Anti-Müllerian Hormone paradox in PCOS
PCOS is the most common female reproductive disorder and can have a significant negative impact on a woman’s chances of conceiving. Ironically, women with PCOS often have high levels of Anti-Müllerian Hormone (AMH). AMH is a measurement of the reserve of follicles a woman has in her ovaries, which is often used to determine a woman’s fertility and chances of conception. This is due to the large number of immature follicles that have developed in the ovaries. In most instances a higher AMH value would be a positive indicator of fertility as it indicates a higher ovarian reserve, but in women with PCOS a high AMH is not always a good thing. In fact, a higher AMH in women with PCOS is associated with higher testosterone levels and a reduced chance of conceiving.
Inflammation in PCOS
The high levels of insulin and high blood glucose that accompany insulin resistance can promote inflammation in women with PCOS, and the disorder is considered an inflammatory condition. Women with PCOS often have elevated levels of key markers of inflammation and these higher levels of inflammation are often accompanied by higher androgen levels. While high insulin and blood glucose promotes inflammation, this inflammation can then cause insulin resistance to become even worse – leading to a vicious cycle of elevated insulin level causing inflammation that then worsens insulin resistance. Therefore testing for, and addressing inflammation, is crucial when addressing PCOS.
The neutrophil to lymphocyte ratio (NLR) is a key marker of inflammation that is often elevated in women with PCOS, even those women with PCOS who are a normal weight. This suggests that the inflammation seen in PCOS is not a result of being overweight, but due to the metabolic imbalances that drive PCOS.
Measuring Insulin Resistance
Insulin resistance can be considered the key imbalance that drives PCOS in most women with the condition, and any treatment protocol must test for markers of insulin resistance and focus on treating this root imbalance. Addressing insulin resistance first and foremost can then have a beneficial impact on the other hormonal imbalances.
The degree of insulin resistance can be measured by testing fasting blood glucose and HbA1c. Fasting blood glucose measures the actual concentration of glucose in the blood before breakfast at any given day, whereas HbA1c is an indirect measure of your blood glucose elevations over the previous 2-3 months. The combination of these two blood markers therefore provides a reliable measure of the degree of insulin resistance.
Women with PCOS, even women who are a normal weight and therefore should be unlikely to suffer from a metabolic disorder, have higher HbA1C levels than women of the same weight without PCOS. Women with PCOS who are a normal weight are over 6 times more likely to have elevated HbA1c levels, and young women with PCOS often have HbA1C levels similar to much older women.
Nutrient Deficiencies and PCOS
Nutritional interventions to support PCOS should focus on key nutrients that are known to play a role in improving insulin resistance: vitamin D and magnesium.
Vitamin D plays an important role in improving the sensitivity of the body’s cells to insulin, therefore reducing insulin resistance. Women with PCOS who had lower vitamin D levels were found to have an even higher degree of insulin resistance. Similarly, the mineral magnesium plays an important role in insulin signalling in the body. Women with PCOS were more likely than women without PCOS to have low levels of magnesium and the lower their magnesium the worse their insulin resistance. Therefore testing for, and treating, deficiencies of vitamin D and magnesium is a key nutritional strategy in supporting the metabolic imbalances that drive PCOS.
Women with PCOS are often prescribed the diabetes medication Metformin to address insulin resistance and improve chances of conceiving. Metformin use can lead to a deficiency in both vitamin B12 and folate. As these two vitamins play an important role in fertility and conceptual health, it is important to test levels of these two nutrients regularly if using metformin.
Don’t forget to check your thyroid
Thyroid health may appear unrelated to PCOS, yet research indicates that women with PCOS are 3 times more likely to suffer from low thyroid function than women without PCOS. As thyroid health is crucial in supporting fertility and during pregnancy, women with PCOS who are trying to conceive should also monitor thyroid hormone levels.
Dietary and lifestyle changes to support PCOS
Testing for the key imbalances discussed above will provide you with the necessary information to develop a personalised and focused protocol of dietary and lifestyle changes to address PCOS.
Dietary changes can have a big impact on insulin resistance and insulin levels. Avoiding sugar and replacing refined carbohydrates with high-fibre slow release carbohydrates can reduce the amount of glucose and insulin produced after a meal and has been shown to result in a 20% reduction in androgen levels.
The timing of meals seems to have a significant impact on PCOS. A study found that when women with PCOS ate their largest meal of the day at breakfast time (980 calories) and smallest meal at dinner time (190 calories) for 90 days their free testosterone levels reduced by 50% and SHBG levels increased by 105%.
Exercise is important in supporting weight loss and also in addressing insulin resistance and has been shown to reduce levels of inflammation in women with PCOS. Resistance training is more effective than cardiovascular exercise at improving insulin resistance so it is important to incorporate resistance training using either bodyweight or free weights into any exercise regime.
Break the vicious cycle of insulin resistance and inflammation by incorporating anti-inflammatory foods into the diet. Anti-inflammatory foods include extra virgin olive oil, omega-3 fats from oily fish, turmeric and green leafy vegetables.
Specific foods have been shown to have a powerful impact on the hormonal imbalances we see in PCOS. Cinnamon can help to treat insulin resistance and one study found that taking 0.5g of cinnamon with every meal for 6 months saw an improvement in ovulation and menstrual regularity. Another piece of research found that eating 30g of milled flaxseed every day for 12 weeks led to an improvement in insulin resistance and reduction in inflammation in women with PCOS.
The good bacteria that live in our digestive system appear to have a key role in PCOS. While insulin resistance appears to be the root imbalance driving the condition, there is evidence that this insulin resistance is partially caused by imbalances in these good bacteria. So eating a diet rich in fermented foods such as live natural yoghurt, kefir, kimchi and sauerkraut could have benefits for women with PCOS.
Testing for PCOS and fertility
If you're experiencing symptoms of PCOS, or want to learn more about how that may affect your fertility or overall health, you can book a blood test directly via Melio, at a time that suits you.
A trained health professional at one of our partner clinics will perform the blood draw, and send the sample to one of our UKAS accredited labs. All test results are individually checked by one of our in-house doctors, who will also write you a personal medical report with any further advice and guidance you may need.
Learn more and order your Melio blood test by clicking on a product below, or use the chat button if you’d like talk to one of our specially trained advisors for more information.
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