What is Polycystic Ovary Syndrome?
Polycystic (literally, many cysts) ovary syndrome (PCOS or PCO) is a complex condition, characterise by hormonal imbalances that affects the ovaries (the organs in a woman’s body that produce eggs). In PCOS, the ovaries are generally bigger than average. The outer surface of the ovary has an abnormally large number of small follicles (the sac of fluid that grows around the egg under the influence of stimulating hormones from the brain).The ovaries are polycystic, with many small follicles scattered under the surface of the ovary (usually more than 10 or 15 in each ovary) and almost none in the middle of the ovary. In PCOS, these follicles remain immature, never growing to full development or ovulating to produce an egg capable of being fertilised.
This means that ovulation (releasing an egg) may rarely occur and can therefore lead to reduced fertility. In addition, periods may be irregular or absent. Other features include excess weight and body hair.
What are the symptoms of Polycystic Ovary Syndrome?
Symptoms that occur if you do not ovulate
- Absent, irregular or light periods– periods can be as frequent as every five to six weeks, but might only occur once or twice a year, if at all
- Fertility problems – you need to ovulate to become pregnant. You may not ovulate each month, and some women with PCOS do not ovulate at all. PCOS is one of the most common causes of infertility.
Symptoms that can occur if you make too much testosterone (male hormone)
- increased facial and body hair (hirsutism): usually found under the chin, on the upper lip, forearms, lower legs and on the abdomen (usually a vertical line of hair up to the umbilicus) .This is the only symptom in some cases.
- Acne: which may persist beyond the normal teenage years.
- Thinning of scalp hair (similar to male pattern baldness) occurs in some cases .
- Being overweight or obese: a common finding in women with PCOS because their body cells are resistant to the sugar-control hormone insulin. This insulin resistance prevents cells using sugar in the blood normally and the sugar is stored as fat instead
- Miscarriage (sometimes recurrent): one of the hormonal abnormalities in PCOS, a raised level of luteinising hormone (LH – a hormone produced by the brain that affects ovary function), seems to be linked with miscarriage. Women with raised LH have a higher miscarriage rate (65 per cent of pregnancies end in miscarriage) compared with those who have normal LH values (around 12 per cent miscarriage rate).
- Depression or poor self-esteem may develop as a result of the other symptoms.
At least two of the following occur in PCOS, and often all three:
- At least 12 follicles (tiny cysts) develop in your ovaries.
- The balance of hormones that you make in the ovaries is altered. In particular, your ovaries make more testosterone (male hormone) than normal. The main hormones that are made in the ovaries are oestrogen and progesterone – the main female hormones, but the ovaries also normally make small amounts of male hormones (androgens) such as testosterone.
- You do not ovulate each month. Some women do not ovulate at all. In PCOS, although the ovaries usually have many follicles, they do not develop fully and so ovulation often does not occur. If you do not ovulate then you do not have a period.
Therefore, it is possible to have polycystic ovaries without the typical symptoms that are in the syndrome. It is also possible to have PCOS without multiple cysts in the ovary.
PCOS is relatively common among infertile women. If affects up to 10 per cent of all women between the ages of 15 and 50. In the general population, around 25 per cent of women will have polycystic ovaries seen on an ultrasound examination. But most have no other symptoms or signs of PCOS and have no health problems. The ultrasound appearance is also found in up to 14 per cent of women on the oral contraceptive pill.
What causes polycystic ovary syndrome?
The exact cause is not totally clear. Several factors probably play a part. These include the following:
1. A small increase in the amount of insulin and cellular resistance to its actions– insulin is a hormone that you make in your pancreas and its main role is to control your blood sugar level. Insulin acts mainly on fat and muscle cells to stimulate them to take in sugar (glucose) when your blood sugar level rises (as excess levels are toxic to cells). Insulin also stimulates the ovaries to produce testosterone (male hormone).
Women with PCOS have what is called insulin resistance, meaning that cells in the body are resistant to the effect of a normal level of insulin. Thus, more insulin is produced to keep the blood sugar normal. Raised levels of insulin in the bloodstream are thought to be the main underlying reason why PCOS develops because this causes the ovaries to make too much testosterone. A high level of insulin and testosterone interfere with the normal development of follicles in the ovaries. As a result, many follicles tend to develop but often do not develop fully. This causes problems with ovulation: hence period problems and reduced fertility. Increased testosterone levels in the blood cause excess hair growth on the body and thinning of the scalp hair.
2. Raised luteinising hormone (LH) in the early part of the menstrual cycle- This hormone is made in the pituitary gland and stimulates the ovaries to ovulate and works alongside insulin to promote testosterone production. A high level of LH is found in about 4 in 10 women with PCOS. A high LH level combined with a high insulin level means that the ovaries are likely to produce too much testosterone.
3. Lower amounts of the blood protein that binds to and carries all sex hormones (called sex-hormone-binding globulin)– this means that testosterone levels are higher and therefore more active. Sex-hormone-binding globulin levels are reduced in insulin resistance (meaning there are high insulin levels).
4. Hereditary factors- one or more genes may make you more prone to developing PCOS. PCOS is not strictly inherited from parents to children, but it may run in some families.
5. Weight– Being overweight or obese is not the underlying cause of PCOS. However, if you are overweight or obese, excess fat can make insulin resistance worse, a contributing factor to PCOS. This may then cause the level of insulin to not only rise even further, but high levels of insulin can contribute to further weight gain, producing a ‘vicious cycle’.
Risk factors for PCOS
- a tendency in the family towards Type 2 diabetes (non-insulin dependent diabetes)
- a close relative who already has PCOS
- a tendency towards early baldness in the men in the family (before 30 years of age).
Nutritional and lifestyle approaches to PCOS
Research has shown that weight control improves many aspects of PCOS. Menstrual cycles become more regular, testosterone levels are reduced, fat and sugar metabolism improves, and spontaneous pregnancy may follow. Obese patients do not have to reach the normal body mass index; a weight reduction of even a few percent has clinical benefits. This is because visceral fat (intra-abdominal fat located inside the abdominal cavity, packed between the organs) is metabolically more hormonally active, and weight loss of a few percent is associated with significant loss of visceral fat.
Weight management through nutrition and exercise is now recommended to all overweight/obese women with PCOS (Kovacs 2006).
So, here are some tips to help reduce the hormonal imbalances associated with PCOS:
1. Research has shown that fat intake should be restricted to not more than 30% of total calories with a low proportion of saturated fat, which is found mostly in animal products such as meat and dairy. Healthy fats such as olive oil, nuts/seeds, avocados, and fish oil, and avocado are important parts of a PCOS–friendly diet however (Farshchi et al 2007).
2. Choose whole grain carbohydrates. The insulin level in your blood goes up after you eat. It increase the most after you eat or drink something that contains carbohydrates. Carbohydrates are found in grains (such as bread, pasta, rice, cereal, and potatoes), vegetables, fruits and drinks such as soda and juice. Even if you eat two foods that have the same amount of carbohydrate, they may have a different effect on your insulin level. This effect has a lot to do with the type of carbohydrate the food has.
Whole grain carbohydrates which contain fibre such as brown rice, whole wheat bread and pasta, oats, barley, etc. have a low Glycaemic Index (GI). GI is a term used to describe how a food affects blood sugar; the higher a food raises blood sugar, the higher the glycaemic index. The benefit of consuming low GI foods is that it helps keep your insulin level down, and also keeps hunger at bay for longer, thus aiding weight management. Sugary foods or refined grains (such as white bread, white rice and white pasta) on the other hand have a high GI and can cause insulin levels to go up and are also not very filling (which means you may feel hungry again shortly after eating them.
3. Always have some protein with each meal or snack– combining a carbohydrate food with protein lowers the GI because protein slows the release of sugar from foods into the bloodstream. This helps reduce blood sugar spikes and therefore helps prevent high insulin levels. Protein can be found in lean meats, fish, poultry, dairy products, tofu, eggs, beans, nuts and seeds. Try to consume plenty of plant proteins which are often high in fibre and low in fat, rather than just sticking to animal proteins.
4. Have balanced meals containing carbohydrates, protein, and fat – combining foods that contain protein or fat with a carbohydrate will help to slow down the absorption of the carbohydrate and keep insulin levels low. For example, have almond butter or hummus on bread rather than just a piece of bread by itself. A typical plate of food should consist of ¼ carbohydrates, ¼ protein and the remaining ½ plate of vegetables!
5. Have smaller, more frequent meals (every 3-4 hours) to help control blood glucose levels. Your insulin will go up much more if you have 3 cups of pasta than if you have 1 cup of pasta. This means it’s usually better to have small meals and snacks during the day than it is to have fewer really big meals to keep your insulin level lower.
6. Exercise– Research has shown that at least 150 minutes of moderate or vigorous activity per week for diabetes prevention. This is because exercise helps your cells become more receptive to the effects of insulin which in turn helps lower insulin levels (Knowler et al 2002).
7. Supplements– there are a number of supplements which can be very helpful to rebalance hormones. Recommendations are based on your individual health profile and are discussed at your visit.
Cahill D (2010) Polycystic ovary syndrome (PCOS) last accessed 21.3.2013 online at http://www.netdoctor.co.uk/womenshealth/facts/pcos.htm
Farshchi H Rane A Love A Kennedy RL (2007) Diet and nutrition in polycystic ovary syndrome (PCOS): pointers for nutritional management. J Obstet Gynaecol 27 8 762-73
Kenny T (2010) Polycystic Ovary Syndrome last accessed 21.3.2013 online at http://www.patient.co.uk/health/Polycystic-Ovary-Syndrome.htm
Knowler WC Barrett-Connor E Fowler SE et al (2002) Diabetes Prevention Program Research Group. Reduction in the incidence of type 2 diabetes with lifestyle intervention or metformin. N Engl J Med 346 393-403
Kovacs P (2006) Viewpoint: Lifestyle Modification is First-Line Treatment for PCOS last accessed 21.3.2013 online at http://www.medscape.com/viewarticle/522390