Polycystic ovary syndrome (PCOS) is a hormone disorder defined by a group of signs and symptoms. PCOS affects 7–10% of women of childbearing age and is the most common cause of infertility. PCOS is the most common hormonal disorder among women of reproductive age, but many women don’t know they have it.
The exact causes of PCOS are unknown. It is thought that there are many potential causes and these may be different between individual girls or women. Androgen excess (male hormone excess), seen in 60-80% of girls and women with PCOS, is a key problem in the disorder and likely comes from ovaries in most women. Insulin resistance or elevated insulin levels may worsen androgen excess. Abnormalities in how the brain or pituitary gland communicate with the ovaries may also lead to androgen overproduction. Other hormones from the ovary or fat tissue may also be involved.
PCOS seems to be inherited. Female relatives or children of patients with PCOS are at increased risk for having PCOS. Environmental risk factors—including low birth weight, rapid weight gain in infancy, early pubic hair and puberty development, childhood obesity, excess adult weight, and unhealthy lifestyle—are also important and may interact with genes to lead to PCOS.
Along with irregular periods, the first signs of PCOS may be the growth of facial and male-patterned body hair, acne, thinning scalp hair, and weight gain. Weight gain, however, is not always present. Normal-weight women can also have PCOS.
In addition to assessing signs and symptoms of PCOS, medical providers take a medical history, perform a physical exam, and check blood hormone levels (including testosterone). They may also perform an ovarian ultrasound. Other tests looking for complication of PCOS may also be done, such as glucose tolerance test or a mental health screening survey.
Other disorders that mimic the clinical features of PCOS should be excluded: thyroid disease, high prolactin levels, and non-classical congenital adrenal hyperplasia.
signs of PCOS include:
Male hormone (androgen) excess
Problems with ovulation
Ultrasound findings
Some conditions related to PCOS are potentially serious. Many women with PCOS have decreased sensitivity to insulin, the hormone that regulates glucose (sugar) in the blood. This condition, known as insulin resistance, is a major risk factor for type 2 diabetes. Women with PCOS often have type 2 diabetes, which occurs more frequently in women with PCOS. Signs of insulin resistance include weight gain (especially around the waist), acanthosis nigricans (skin thickening around the neck, armpits, belly, button, and other creases), and skin tags.
The combination of type 2 diabetes mellitus, low HDL levels (good cholesterol), and high levels of LDL and triglycerides (bad cholesterol and blood fat) in women with PCOS may increase the risk of heart attack or stroke in women with PCOS.
Women with PCOS who are overweight or obese can also develop a condition called obstructive sleep apnea, when breathing stops repeatedly during sleep. This condition can worsen the insulin resistance and cardiovascular problems of women with PCOS.
Women with PCOS may also develop fat accumulation in the liver (non-alcoholic fatty liver disease), which can lead to liver damage (non-alcoholic steatohepatitis) and fibrosis over time.
Because of irregular menstrual cycles and lack of ovulation, the lining of the uterus may not shed as often as it should. Left untreated, this may increase the risk of cancer of the uterine lining (endometrium).
Adolescents and women with PCOS are also at higher risk for depression and anxiety. Women with PCOS, especially who are overweight, may experience pregnancy complications, including gestational diabetes, preterm delivery, or pre-eclampsia.