Polycystic Ovary Syndrome (PCOS)
Polycystic ovary syndrome affects millions of women worldwide, causing irregular periods, hormonal imbalances, and fertility challenges—yet up to 70% of cases remain undiagnosed.
Table of contents
- What is Polycystic Ovary Syndrome?
- Signs and Symptoms
- What Causes PCOS?
- How is PCOS Diagnosed?
- Associated Health Problems
- Treatment Options
- Lifestyle Changes and Self-Care
- PCOS and Fertility
PCOS, Stein-Leventhal Syndrome
- Ovaries
- Reproductive system
- Endocrine system
What is Polycystic Ovary Syndrome?
Polycystic ovary syndrome is a common condition that affects how a woman’s ovaries work. It is a hormonal imbalance that occurs when the ovaries create excess amounts of certain hormones, particularly androgens (male-type hormones that women normally make in smaller amounts)[1][2]. This hormonal disturbance causes various problems throughout the body.
PCOS is one of the most common conditions affecting women of reproductive age. It affects an estimated 6 to 13% of women worldwide, though the exact numbers vary depending on which diagnostic criteria are used[5]. In the United States alone, about 7% of women have PCOS, making it the most common endocrine disorder among females of childbearing age[3][15]. Despite being so widespread, up to 70% of women with PCOS remain undiagnosed globally[5].
The name “polycystic” refers to the many small fluid-filled sacs called follicles that can develop on the ovaries. These follicles contain immature eggs that often fail to be released during ovulation[1]. However, it’s important to know that despite the name, you don’t necessarily need to have cysts on your ovaries to have PCOS, and the cysts themselves are not dangerous or painful[2][4].
PCOS usually starts during adolescence, often around the time of the first menstrual period, but symptoms may not become noticeable until later[5]. Most people are diagnosed in their 20s or 30s, particularly when they are trying to get pregnant[2].
Signs and Symptoms
The symptoms of PCOS can vary greatly from person to person. Some women experience only mild symptoms, while others have more severe problems. Some may not even realize they have the condition until they have trouble getting pregnant or experience unexplained weight gain[2]. The symptoms can also change over time and often occur without a clear trigger[5].
The most common signs and symptoms of PCOS include[1][2][4]:
- Irregular periods: This is one of the most common signs. You may have very few menstrual periods (fewer than nine per year), no periods at all, or periods that last many days or are unpredictable. This happens because the ovaries don’t regularly release eggs, a process called ovulation.
- Excess hair growth: Up to 70% of women with PCOS develop excessive hair on the face, chest, back, abdomen, or other parts of the body. This condition is called hirsutism[2].
- Acne: PCOS can cause acne, especially on the back, chest, and face. This acne may continue well past the teenage years and can be difficult to treat[2].
- Weight gain and difficulty losing weight: Between 40% and 80% of people with PCOS struggle with obesity or have trouble maintaining a healthy weight[2].
- Thinning hair or hair loss: Some women may lose patches of hair on their head or experience male-pattern baldness[2].
- Darkened skin patches: You may develop patches of thick, dark, velvety skin in body folds and creases, such as the neck, armpits, groin, or under the breasts. This is known as acanthosis nigricans[2][4].
- Skin tags: These are small flaps of extra skin, often found in the armpits or on the neck[2].
- Infertility: PCOS is one of the most common causes of female infertility. Not ovulating regularly makes it difficult to become pregnant[2][5].
It’s important to note that symptoms often become apparent during the late teens or early 20s, though they can develop later in life[4]. Some women with PCOS have few or even no symptoms and may not discover they have the condition until they face fertility challenges[2].
What Causes PCOS?
The exact cause of PCOS is not fully understood, but researchers believe it results from a complex interaction of genetic and environmental factors[3]. Several factors are thought to contribute to the development of PCOS:
Genetics: PCOS tends to run in families, suggesting that genetic factors play an important role[4][6]. If your mother or sister has PCOS, you may be at higher risk of developing it yourself.
Insulin resistance: Many women with PCOS have insulin resistance, meaning their bodies produce insulin (a hormone that helps control blood sugar levels) but cannot use it effectively[4][6]. When cells don’t respond properly to insulin, the body produces more of it to compensate. These higher insulin levels can cause the ovaries to produce more androgens, which leads to many of the symptoms of PCOS[15]. Being overweight or obese can worsen insulin resistance[4].
Hormonal imbalances: The condition is linked to imbalances in reproductive hormones, particularly elevated levels of androgens and disrupted signaling between the brain, pituitary gland, and ovaries[3].
It’s important to understand that PCOS is related to abnormal hormone levels in the body, including high levels of insulin and androgens[4]. These imbalances create a cycle that perpetuates the symptoms and complications of the condition.
How is PCOS Diagnosed?
There is no single specific test to diagnose PCOS. Instead, healthcare providers use a combination of medical history, physical examination, and various tests to make the diagnosis[6][9]. PCOS is considered a diagnosis of exclusion, meaning other conditions that could cause similar symptoms must be ruled out first[3].
Most medical guidelines recommend using the Rotterdam criteria for diagnosing PCOS. According to these criteria, a diagnosis is made when you have at least two of the following three features[3][15]:
- Irregular periods or absence of ovulation
- Excess androgen levels (either seen through blood tests or physical signs like excessive hair growth or acne)
- Polycystic ovaries visible on ultrasound
The diagnostic process typically includes[6][9]:
Medical history and physical exam: Your healthcare provider will ask about your symptoms, menstrual cycles, weight changes, family health history, and any medications you take. They will perform a physical examination to check for signs of excess hair growth, insulin resistance, acne, and other physical manifestations of PCOS.
Pelvic exam: During this examination, the provider checks your reproductive organs for any abnormalities, masses, or other changes[9].
Blood tests: These measure hormone levels to check for elevated androgens and to rule out other conditions that can mimic PCOS symptoms. Blood tests may also check cholesterol levels, blood sugar, and insulin levels[9].
Pelvic ultrasound: This imaging test uses sound waves to create pictures of your ovaries and uterus. It can show whether you have multiple follicles on your ovaries and can check the thickness of the lining of your uterus[9].
All women with suspected PCOS should be screened for thyroid disease, elevated prolactin levels, and a condition called nonclassical congenital adrenal hyperplasia, as these can cause similar symptoms[15].
For adolescent girls, it may be reasonable to delay evaluation for PCOS until two years after their first period, as irregular cycles are common during this time. When diagnosing PCOS in teenagers, it’s recommended that all three Rotterdam criteria be met[15].
Associated Health Problems
PCOS is associated with an increased risk of several other health conditions, making it important to monitor your overall health if you have been diagnosed with this syndrome[3][4][6]:
Type 2 diabetes: More than half of women with PCOS develop type 2 diabetes by age 40[7]. Women with PCOS are four times more likely to develop diabetes than the general population[15]. This increased risk is largely due to insulin resistance.
Metabolic syndrome: This is a cluster of conditions that includes high blood pressure, high blood sugar, abnormal cholesterol levels, and excess body fat around the waist. Metabolic syndrome is twice as common in women with PCOS compared to the general population[3][15].
Heart disease: Women with PCOS have an increased risk of developing cardiovascular problems, and this risk increases with age[4][6].
High blood pressure and abnormal cholesterol levels: These conditions contribute to the increased risk of heart disease[4][6].
Endometrial cancer: Women with PCOS who don’t have regular periods have an increased risk of developing cancer of the uterine lining. This happens because irregular ovulation can cause the lining to build up without being shed regularly[4][10].
Sleep apnea: This is a disorder that causes you to repeatedly stop breathing during sleep. It’s more common in women with PCOS[3][6].
Mental health conditions: PCOS is linked to higher rates of depression and anxiety. The biological and psychological effects of PCOS, particularly those related to body image, weight gain, and infertility, can lead to mental health challenges and social stigma[5][6].
Fatty liver disease: Women with PCOS are at increased risk of developing metabolic dysfunction-associated steatotic liver disease[3].
Not everyone with PCOS will develop all these problems, but it’s important to work with your healthcare provider to monitor your health so that any emerging conditions can be detected and treated early[6].
Treatment Options
There is no cure for PCOS, but the symptoms can be managed effectively[4][10]. Treatment is individualized based on your specific symptoms, whether you wish to become pregnant, and your overall health[12]. The main treatment options include:
Lifestyle modifications: For women who are overweight, weight loss is considered first-line treatment[13]. Even losing just 5% of your body weight can lead to significant improvement in PCOS symptoms[10][20]. Diet and exercise are critical for symptom improvement and reducing long-term health risks[3].
Hormonal contraceptives: Birth control pills are often the first-line treatment for women who are not trying to get pregnant. They help regulate menstrual cycles, reduce excess hair growth and acne, and lower the risk of endometrial cancer[10][13]. Other hormonal methods, such as an intrauterine system, can also help protect the uterine lining[10].
Metformin: This medication is commonly used to treat type 2 diabetes, but it can also help women with PCOS by lowering insulin and blood sugar levels. Metformin can help regulate menstrual cycles and may improve fertility, though it has limited benefits for treating excess hair growth or acne[10][13].
Fertility medications: For women trying to become pregnant, medications such as clomiphene or letrozole may be prescribed to stimulate ovulation[10][13]. Letrozole may result in higher rates of ovulation and live births compared to clomiphene[15].
Anti-androgen medications: Drugs like spironolactone can help reduce excessive hair growth and improve acne by blocking the effects of androgens[13].
Hair removal treatments: A cream called eflornithine can slow down unwanted facial hair growth, though it doesn’t remove existing hair[10][20].
Progestogen therapy: For women who are not taking birth control pills, courses of progestogen tablets can be given every few months to induce periods and protect the uterine lining[10].
Treatment decisions should be made in partnership with your healthcare provider, taking into account your individual symptoms, health concerns, and reproductive goals.
Lifestyle Changes and Self-Care
Lifestyle changes are the most effective way to manage PCOS and reduce the severity of symptoms[19]. Making healthy choices can improve both physical and mental health and may reduce the risk of long-term complications:
Diet and nutrition: Eating a healthy, balanced diet is essential. Focus on including plenty of fruits and vegetables (at least five portions daily), whole grains such as wholemeal bread and brown rice, and lean proteins like fish and chicken[10][20]. Diets that emphasize whole plant-based foods, such as the Mediterranean diet, may be particularly beneficial for women with PCOS[22]. These diets balance fiber-rich foods, healthy fats, and foods rich in antioxidants.
Physical activity: Regular exercise is an important part of managing PCOS. It can improve symptoms even without significant weight loss. Physical activity increases energy levels, helps with weight management, improves emotional wellbeing, reduces androgen production, and can improve menstrual cycle regularity and fertility[19]. Aim for at least 30 minutes of physical activity most days of the week. The type of activity is less important than finding something you enjoy and can stick with. A combination of cardiovascular exercise and strength training is recommended[19].
Weight management: For women who are overweight, losing even a small amount of weight can make a significant difference. Weight loss of just 5% can lead to improvements in insulin sensitivity, hormone levels, menstrual regularity, and fertility[16][19].
Stress management: PCOS can affect mental health, and managing stress is important. Consider relaxation techniques, mindfulness, or speaking with a mental health professional if you’re struggling with anxiety or depression.
Making lifestyle changes can be challenging, especially with PCOS. Research shows that women with PCOS are more likely to succeed in making and maintaining these changes when they have strong support from healthcare professionals, family, and friends[19].
PCOS and Fertility
PCOS is one of the most common causes of female infertility because irregular or absent ovulation makes it difficult to become pregnant[2][3]. However, it’s important to know that many women with PCOS can and do become pregnant, either naturally or with medical assistance[4][6].
For women with PCOS who wish to become pregnant:
Lifestyle improvements: Achieving a healthy weight through diet and exercise can improve fertility. Even modest weight loss can restore ovulation in some women[16].
Fertility medications: Clomiphene is often the first medication recommended to encourage the release of an egg each month[10][12]. Letrozole is another option that may be more effective than clomiphene for some women[13]. If these oral medications don’t work, injectable medications called gonadotrophins may be tried, though these carry a higher risk of multiple pregnancies[10].
Metformin: This medication may help with fertility by improving insulin sensitivity and lowering the risk of miscarriage, though it’s not primarily used as a fertility treatment[10].
Surgical options: In some cases, a procedure called laparoscopic ovarian drilling may be recommended if medications haven’t worked[4].
If you have PCOS and are not trying to get pregnant but are sexually active, it’s important to use effective contraception, especially if you’re taking medications like metformin that can improve fertility[10][20].
