PCOS often correlates with insulin resistance (where the body’s cells and tissues do not respond normally to the presence of insulin). This may be caused by lifestyle and diet. In a healthy body, blood glucose is converted into energy. However, insulin resistance prevents glucose entering the body’s cells. Instead, the excess glucose in the blood is taken up by the liver and converted into fat, which increases overall fatty tissue. Women suffering from PCOS are more prone to being overweight, but even lean patients have a propensity to insulin resistance.
What’s more, elevated blood insulin (a response to high blood glucose levels) causes the ovaries to significantly increase production of testosterone. This excess, in turn, slows or stops ovulation, marking the beginning of anovulatory cycles.
Finally, elevated insulin levels also affect the conversion of male hormones into oestrogen in the fatty tissue. Elevated oestrogen levels not only result in poor follicle development, and less chance of ovulation. It also causes increased sensitivity of the pituitary gland and increases Luteinising Hormone (LH). Elevated LH levels can promote further increases in testosterone production.
