Polycystic ovary syndrome (PCOS) is a hormonal disorder common among women of reproductive age. Women with PCOS may have infrequent or prolonged menstrual periods or excess male hormone (androgen) levels. The ovaries may develop numerous small collections of fluid (follicles) and fail to regularly release eggs.

The exact cause of PCOS is unknown. Early diagnosis and treatment along with weight loss may reduce the risk of long-term complications such as type 2 diabetes and heart disease.

Signs and symptoms of PCOS often develop around the time of the first menstrual period during puberty. Sometimes PCOS develops later, for example, in response to substantial weight gain.

Signs and symptoms of PCOS vary. A diagnosis of PCOS is made when you experience at least two of these signs:

• Irregular periods. Infrequent, irregular or prolonged menstrual cycles are the most common sign of PCOS. For example, you might have fewer than nine periods a year, more than 35 days between periods and abnormally heavy periods.
• Excess androgen. Elevated levels of male hormones may result in physical signs, such as excess facial and body hair (hirsutism), and occasionally severe acne and male-pattern baldness.
• Polycystic ovaries. Your ovaries might be enlarged and contain follicles that surround the eggs. As a result, the ovaries might fail to function regularly.

PCOS signs and symptoms are typically more severe if you're obese.

When to see a doctor

See your doctor if you have concerns about your menstrual periods, if you're experiencing infertility or if you have signs of excess androgen such as worsening hirsutism, acne and male-pattern baldness.

The exact cause of PCOS isn't known. Factors that might play a role include:

• Excess insulin. Insulin is the hormone produced in the pancreas that allows cells to use sugar, your body's primary energy supply. If your cells become resistant to the action of insulin, then your blood sugar levels can rise and your body might produce more insulin. Excess insulin might increase androgen production, causing difficulty with ovulation.
• Low-grade inflammation. This term is used to describe white blood cells' production of substances to fight infection. Research has shown that women with PCOS have a type of low-grade inflammation that stimulates polycystic ovaries to produce androgens, which can lead to heart and blood vessel problems.
• Heredity. Research suggests that certain genes might be linked to PCOS.
• Excess androgen. The ovaries produce abnormally high levels of androgen, resulting in hirsutism and acne.

Complications of PCOS can include:

• Infertility
• Gestational diabetes or pregnancy-induced high blood pressure
• Miscarriage or premature birth
• Nonalcoholic steatohepatitis — a severe liver inflammation caused by fat accumulation in the liver
• Metabolic syndrome — a cluster of conditions including high blood pressure, high blood sugar, and abnormal cholesterol or triglyceride levels that significantly increase your risk of cardiovascular disease
• Type 2 diabetes or prediabetes
• Sleep apnea
• Depression, anxiety and eating disorders
• Abnormal uterine bleeding
• Cancer of the uterine lining (endometrial cancer)

Obesity is associated with PCOS and can worsen complications of the disorder.

There's no test to definitively diagnose PCOS. Your doctor is likely to start with a discussion of your medical history, including your menstrual periods and weight changes. A physical exam will include checking for signs of excess hair growth, insulin resistance and acne.

Your doctor might then recommend:

• A pelvic exam. The doctor visually and manually inspects your reproductive organs for masses, growths or other abnormalities.
• Blood tests. Your blood may be analyzed to measure hormone levels. This testing can exclude possible causes of menstrual abnormalities or androgen excess that mimics PCOS. You might have additional blood testing to measure glucose tolerance and fasting cholesterol and triglyceride levels.
• An ultrasound. Your doctor checks the appearance of your ovaries and the thickness of the lining of your uterus. A wandlike device (transducer) is placed in your vagina (transvaginal ultrasound). The transducer emits sound waves that are translated into images on a computer screen.

If you have a diagnosis of PCOS, your doctor might recommend additional tests for complications. Those tests can include:

• Periodic checks of blood pressure, glucose tolerance, and cholesterol and triglyceride levels
• Screening for depression and anxiety
• Screening for obstructive sleep apnea

PCOS treatment focuses on managing your individual concerns, such as infertility, hirsutism, acne or obesity. Specific treatment might involve lifestyle changes or medication.

Lifestyle changes

Your doctor may recommend weight loss through a low-calorie diet combined with moderate exercise activities. Even a modest reduction in your weight — for example, losing 5 percent of your body weight — might improve your condition. Losing weight may also increase the effectiveness of medications your doctor recommends for PCOS, and can help with infertility.

Medications

To regulate your menstrual cycle, your doctor might recommend:

• Combination birth control pills. Pills that contain estrogen and progestin decrease androgen production and regulate estrogen. Regulating your hormones can lower your risk of endometrial cancer and correct abnormal bleeding, excess hair growth and acne. Instead of pills, you might use a skin patch or vaginal ring that contains a combination of estrogen and progestin.
• Progestin therapy. Taking progestin for 10 to 14 days every one to two months can regulate your periods and protect against endometrial cancer. Progestin therapy doesn't improve androgen levels and won't prevent pregnancy. The progestin-only minipill or progestin-containing intrauterine device is a better choice if you also wish to avoid pregnancy.

To help you ovulate, your doctor might recommend:

• Clomiphene. This oral anti-estrogen medication is taken during the first part of your menstrual cycle.
• Letrozole (Femara). This breast cancer treatment can work to stimulate the ovaries.
• Metformin. This oral medication for type 2 diabetes improves insulin resistance and lowers insulin levels. If you don't become pregnant using clomiphene, your doctor might recommend adding metformin. If you have prediabetes, metformin can also slow the progression to type 2 diabetes and help with weight loss.
• Gonadotropins. These hormone medications are given by injection.

To reduce excessive hair growth, your doctor might recommend:

• Birth control pills. These pills decrease androgen production that can cause excessive hair growth.
• Spironolactone (Aldactone). This medication blocks the effects of androgen on the skin. Spironolactone can cause birth defects, so effective contraception is required while taking this medication. It isn't recommended if you're pregnant or planning to become pregnant.
• Eflornithine (Vaniqa). This cream can slow facial hair growth in women.
• Electrolysis. A tiny needle is inserted into each hair follicle. The needle emits a pulse of electric current to damage and eventually destroy the follicle. You might need multiple treatments.

To help decrease the effects of PCOS, try to:

• Maintain a healthy weight. Weight loss can reduce insulin and androgen levels and may restore ovulation. Ask your doctor about a weight-control program, and meet regularly with a dietitian for help in reaching weight-loss goals.
• Limit carbohydrates. Low-fat, high-carbohydrate diets might increase insulin levels. Ask your doctor about a low-carbohydrate diet if you have PCOS. Choose complex carbohydrates, which raise your blood sugar levels more slowly.
• Be active. Exercise helps lower blood sugar levels. If you have PCOS, increasing your daily activity and participating in a regular exercise program may treat or even prevent insulin resistance and help you keep your weight under control and avoid developing diabetes.

You may be referred to a specialist in female reproductive medicine (gynecologist), a specialist in hormone disorders (endocrinologist) or an infertility specialist (reproductive endocrinologist).

Here's some information to help you get ready for your appointment.

What you can do

• List symptoms you've been having, and for how long
• List all medications, vitamins and supplements you take, including the doses
• List key personal and medical information, including other conditions, recent life changes and stressors
• Prepare questions to ask your doctor
• Keep a record of your menstrual cycles

For PCOS, some basic questions to ask your doctor include:

• What tests do you recommend?
• How does PCOS affect my ability to become pregnant?
• What medications do you recommend to help improve my symptoms or ability to conceive?
• What lifestyle modifications do you recommend to help improve my symptoms or ability to conceive?
• What are the long-term health implications of PCOS?
• I have other medical conditions. How can I best manage them together?

During your appointment, don't hesitate to ask other questions as they occur to you.

What to expect from your doctor

Your doctor is likely to ask you a number of questions, including:

• What are your signs and symptoms? How often do they occur?
• How severe are your symptoms?
• When did each symptom begin?
• When was your last period?
• Have you gained weight since you first started having periods? How much weight did you gain, and when did you gain it?
• Does anything improve or worsen your symptoms?
• Are you trying to become pregnant, or do you wish to become pregnant?
• Has your mother or sister ever been diagnosed with PCOS?