What causes polycystic ovary syndrome (PCOS)?

Diana Meeks
Diana Meeks on behalf of Sigma Nursing
Family Practitioner

The exact cause of polycystic ovary syndrome (PCOS) is unknown, but researchers do know what causes the symptoms. PCOS is caused by an excess production of androgen. Even though all women produce androgen, it is still considered a male hormone and excess levels can cause some difficulties. In an individual with PCOS, the ovaries produce too much androgen, disturbing your period and causing problems like surplus body hair, acne and infertility.

Lately, researchers have been associating carbohydrates with increased insulin and androgen levels. Therefore, doctors often recommend to someone with PCOS that they limit their carbohydrate intake. Rather than eat simple carbohydrates like sugary and processed foods, doctors encourage you to eat complex carbohydrates like whole grains and fiber-filled foods. This will help in weight management and will also help to decrease levels of insulin and androgen.

PCOS can cause many skin and hair symptoms like acne and extra hair growth. However, certain ethnicities do not present any of these outward signs or symptoms. In particular, Northern Europeans and Asians do not usually show symptoms like extra hair growth and acne. Therefore, it is important not only to be tested based on outward symptoms, but also based on risk factors like family history, obesity, diabetes and infertility.

Athough genetic factors are believed to make certain women more susceptible to polycystic ovary syndrome (PCOS), Susan Davis, M.D., a UCLA endocrinologist, notes that lifestyle, including diet and exercise, plays an important role in its severity. In particular, excess weight exacerbates both the reproductive problems and the insulin resistance that is linked to diabetes. "Thus, weight loss through diet and exercise is one of the most important strategies to combat the effects of PCOS."

Polycystic ovary syndrome (PCOS) is thought to result from genetic defects, often in combination with environmental factors. Genetic defects may result in abnormal function of the hormones from the pituitary that regulate ovulation (follicle-stimulating hormone and luteinizing hormone levels), in abnormal development of the follicle, in increased production of male hormones (androgens), and in insulin resistance and excessive production of insulin. All these prevent the ovaries from functioning normally.

Because PCOS is mostly a genetic disorder, the risk of PCOS in family members is high. For example, an estimated 30 percent of mothers, and 50 percent of sisters and daughters of people with PCOS can be affected.

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No one knows the exact cause of polycystic ovarian syndrome (PCOS), but studies are looking at whether it is caused by genetics. Also, because many women with PCOS also have diabetes, studies are examining the relationship between PCOS and the body's ability to produce insulin. There is a lot of evidence that high levels of insulin contribute to increased production of androgen, which worsens the symptoms of PCOS. In addition, the medication Valproate, (used to treat seizures) may cause or worsen the symptoms of PCOS.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.