Insulin resistance Insulin resistance leads to higher levels of blood insulin which makes the ovaries produce too much testosterone hormone (androgens). Too many androgens undermine the development of sacs in the ovaries where eggs develop. The lack of the sacs or follicles causes abnormal or non-existent ovulation. Insulin resistance also makes women put on weight which aggravates the PCOS symptoms making them worse. Hormone imbalance An imbalance in certain hormones is a common symptom of women with PCOS. High testosterone. While women do produce small amounts of testosterone, it is a hormone associated with males and male attributes. High luteinizing hormone (LH). LH stimulates ovulation. If levels are excessively high, the proper functioning of the ovaries is disrupted. Low sex hormone binding globulin (SHBG) levels. SHBG reduces the effects of testosterone in healthy women. High prolactin levels. Prolactin stimulates the production of milk in the breast glands during and after pregnancy. High prolactin is sometimes found in patients with PCOS. No one is sure why these hormone imbalances occur. The source may be the ovary itself or a part of the brain that controls hormone production. It may also be that insulin resistance triggers a series of changes including hormone production. Genes There seems to be a genetic component to PCOS. If a woman’s mother or grandmother had the condition she is more likely to develop it. Scientists have also found that a gene linked to obesity is also linked to susceptibility to PCOS. Bisphenol A (BPA) Researchers have found higher BPA levels in women with PCOS than in women without the condition of the same age. They have also found a significant positive association between androgens and BPS in women with PCOS suggesting that BPA probably has a role in ovarian dysfunction. BPA is a common industrial compound used in dental materials, plastic consumer products, and food and drink packaging. Avoiding BPA filled containers is strongly advised for women with PCOS and any women of reproductive age.