PCOS: The Complete Guide to Polycystic Ovary Syndrome Symptoms, Fertility and Treatment

Polycystic ovary syndrome (PCOS) affects an estimated 10 to 13 percent of women of reproductive age worldwide, according to the World Health Organization, yet up to 70 percent of those affected remain undiagnosed. Many women spend years being told their irregular periods, acne, unwanted hair or weight gain are nothing to worry about. PCOS is far more than an ovarian problem: it is a lifelong hormonal and metabolic condition that affects fertility, heart health, diabetes risk and mental wellbeing.

This guide explains how PCOS is diagnosed, what causes the symptoms, the treatments that help, how to protect your fertility and long-term health, and how to get the care you deserve.

What is PCOS?

PCOS is a common hormonal condition that affects how the ovaries work and how the body handles insulin. The name is misleading. Women with PCOS do not have true cysts on their ovaries. The “cysts” seen on ultrasound are many small follicles, each containing an egg, that have developed but not matured and released an egg as they should.

The key features of PCOS are:

• Irregular or absent ovulation, causing irregular or missed periods
• Higher levels of androgens (hormones such as testosterone that are present in all women but usually in small amounts), causing excess hair growth, acne or scalp hair thinning
• Polycystic-appearing ovaries on ultrasound, or a raised level of anti-Müllerian hormone (AMH) in the blood

In 2023, the International Evidence-based Guideline for PCOS, developed with input from many countries and endorsed by dozens of professional organisations, updated how PCOS should be diagnosed and treated.

What causes PCOS?

The exact cause is not fully understood, but several factors are involved:

• Genetics: PCOS often runs in families. If your mother or sister has it, your risk is higher.
• Insulin resistance: many women with PCOS, including those of healthy weight, have cells that respond poorly to insulin. The body produces more insulin to compensate, and high insulin levels stimulate the ovaries to produce more androgens.
• Hormonal signalling: changes in signals from the brain to the ovaries, including higher luteinising hormone (LH), disrupt egg development.
• Weight: excess weight worsens insulin resistance and symptoms, but PCOS also makes weight gain more likely. It is a two-way relationship, and many women with PCOS are not overweight.
• Environment and early life factors may also play a role.

Symptoms

• Irregular periods (cycles longer than 35 days or fewer than eight periods a year), very light or absent periods, or occasionally heavy, prolonged bleeding
• Difficulty getting pregnant
• Excess hair growth (hirsutism) on the face, chest, abdomen, back or thighs
• Acne, often persistent beyond the teenage years and along the jawline
• Thinning hair or hair loss from the scalp
• Weight gain, especially around the waist, and difficulty losing weight
• Dark, velvety patches of skin in the neck, armpits or groin (acanthosis nigricans), a sign of insulin resistance
• Skin tags
• Low mood, anxiety and poor body image
• Sleep problems, including sleep apnoea

Symptoms vary greatly. Some women have mainly irregular periods; others mainly skin and hair symptoms. Symptoms can appear in the late teens or early twenties, or become noticeable later, for example after stopping the pill.

How PCOS is diagnosed

The 2023 international guideline uses the Rotterdam criteria. In adults, PCOS is diagnosed when two of these three features are present, after other causes are ruled out:

1. Irregular or absent ovulation (irregular periods)
2. Clinical signs of high androgens (hirsutism, acne, scalp hair loss) or high androgen levels on a blood test
3. Polycystic ovaries on ultrasound, or a raised AMH level

If a woman has both irregular periods and signs of high androgens, an ultrasound or AMH test is not needed to diagnose PCOS.

Tests you may have

• Blood tests for testosterone and sex hormone binding globulin (SHBG), ideally when not on hormonal contraception
• Tests to rule out other causes: thyroid function, prolactin, 17-hydroxyprogesterone (for a condition called non-classic congenital adrenal hyperplasia), and pregnancy test
• AMH, which is often raised in PCOS (not recommended for diagnosis in adolescents)
• A transvaginal ultrasound, if needed and appropriate
• Screening for diabetes (an oral glucose tolerance test is preferred) and cholesterol
• Blood pressure, weight and waist measurement

PCOS in teenagers

Irregular periods and acne are common in the first years after periods start, so diagnosing PCOS in adolescents is more difficult. Guidelines recommend that both irregular cycles and high androgens be present, and that ultrasound and AMH are not used for diagnosis within eight years of the first period. Teenagers with symptoms but no clear diagnosis may be considered “at risk” and reviewed later.

Long-term health risks

PCOS is linked with higher risks of:

• Type 2 diabetes and prediabetes: women with PCOS are several times more likely to develop diabetes, regardless of weight. Regular screening is recommended every one to three years.
• Gestational diabetes in pregnancy
• Heart disease risk factors, including high blood pressure and abnormal cholesterol
• Endometrial (womb lining) thickening and cancer: when periods are infrequent, the womb lining builds up without shedding. Having fewer than four periods a year without treatment increases risk.
• Sleep apnoea
• Fatty liver disease
• Depression, anxiety and eating disorders, which are more common in women with PCOS

These risks can be reduced with healthy lifestyle habits, regular checks and appropriate treatment.

Lifestyle: the foundation of treatment

Healthy eating and regular physical activity are recommended for all women with PCOS, whatever their weight. They improve insulin resistance, help regulate periods, support fertility, reduce long-term risks and improve mood.

• No single “PCOS diet” is proven to be best. Focus on a balanced diet with plenty of vegetables, whole grains, legumes, fruit, lean protein and healthy fats, and limit sugary foods and drinks and ultra-processed foods.
• Activity: aim for at least 150 minutes of moderate or 75 minutes of vigorous activity a week, plus muscle-strengthening on two days. More activity brings greater benefits for weight management.
• Weight: for women with excess weight, losing 5 to 10 percent of body weight can restore regular periods and ovulation in some, and improve other symptoms.
• Sleep and stress: poor sleep and chronic stress worsen insulin resistance.
• Weight stigma: the guideline specifically calls on healthcare providers to avoid weight stigma, which is harmful and common in PCOS care.

Medical treatments

Combined oral contraceptive pill

The combined pill is the first-line medical treatment for irregular periods, excess hair and acne in women who do not want to get pregnant. It regulates bleeding, protects the womb lining and reduces androgen effects. Lower-dose pills are recommended. It is not suitable for everyone, for example women with certain risk factors for blood clots or migraine with aura.

Metformin

Metformin, a diabetes medicine, improves insulin sensitivity. It may help with weight, metabolic risk and cycle regularity, particularly in women with a higher BMI, and may be combined with the pill. Gastrointestinal side effects are common at first; starting low and taking it with food, or using the extended-release form, helps.

Protecting the womb lining

If periods are very infrequent and the pill is not used, a course of progestogen tablets every few months to trigger a bleed, or a hormonal intrauterine device (IUD), can protect the womb lining.

Treatments for excess hair

• Shaving, waxing, threading and depilatory creams
• Laser hair removal and electrolysis, which can give long-lasting results (laser works best on darker hair against lighter skin, but newer devices suit darker skin types)
• Eflornithine cream for facial hair, where available
• Anti-androgen medicines such as spironolactone, used alongside effective contraception because they can affect a developing baby

It takes at least six months of treatment to see a change in hair growth, because hair grows in cycles.

Treatments for acne and hair loss

Acne can be treated with standard acne treatments, the combined pill and sometimes anti-androgens. Scalp hair thinning may be helped by minoxidil and treating high androgens. A dermatologist can help with severe or persistent cases.

Weight-loss medicines

GLP-1 receptor agonists such as semaglutide and liraglutide may be considered alongside lifestyle changes for women with PCOS and obesity, according to the 2023 guideline. They should be stopped before trying to conceive, and effective contraception is needed while taking them. Bariatric surgery may be considered for some women with severe obesity.

PCOS and fertility

PCOS is one of the most common causes of infertility due to irregular ovulation, but most women with PCOS can get pregnant, often with relatively simple treatment.

Before trying to conceive

• Take folic acid daily
• Check blood pressure, blood sugar and thyroid
• Stop smoking and limit alcohol
• Aim for a healthy weight if possible, but do not delay seeking help for too long, especially if you are over 35

Ovulation induction

• Letrozole: now the recommended first-line medicine to help women with PCOS ovulate. It results in more live births than clomiphene in studies. Its use in fertility treatment is off-label in some countries.
• Clomiphene citrate: an alternative, sometimes combined with metformin.
• Metformin alone or combined with other treatments.
• Gonadotrophin injections: used if tablets do not work, with careful ultrasound monitoring to reduce the risk of multiple pregnancy.
• Laparoscopic ovarian drilling: a keyhole surgical procedure that may restore ovulation in some women.
• IVF: if other treatments fail or there are other fertility factors. Women with PCOS have a higher risk of ovarian hyperstimulation syndrome (OHSS), so specialist protocols are used.

Pregnancy with PCOS

Women with PCOS have a higher risk of gestational diabetes, high blood pressure, pre-eclampsia and preterm birth. Early screening for diabetes, blood pressure monitoring and good antenatal care are important.

Mental health and quality of life

Depression and anxiety are significantly more common in women with PCOS. Symptoms such as excess hair, acne, weight gain and fertility difficulties can affect self-esteem, body image, relationships and sexual wellbeing. Eating disorders, including binge eating, are also more common. The international guideline recommends screening for depression, anxiety and eating disorders. Talking therapies, support groups and treating symptoms can all help. You are not alone, and your feelings are valid.

PCOS through life

PCOS does not disappear after menopause. Periods may become more regular as women approach their 40s, but metabolic risks, such as diabetes and heart disease, continue and often increase. Ongoing healthy habits and regular checks remain important.

PCOS in different populations

PCOS affects women of all ethnic backgrounds, but features vary. Women of South Asian descent may have more severe insulin resistance and develop diabetes earlier. Hirsutism is assessed differently across ethnic groups, as normal body hair varies. Women in many low- and middle-income countries face particular barriers to diagnosis, and cultural stigma around fertility and appearance can add to distress.

Questions to ask your healthcare provider

• Do my symptoms meet the criteria for PCOS, and have other causes been ruled out?
• Do I need diabetes and cholesterol screening, and how often?
• What are my options for regulating my periods and protecting my womb lining?
• What can be done about excess hair, acne or hair loss?
• If I want to become pregnant, what should I do now and when should I be referred?
• Can I be referred for dietitian, psychological or dermatology support?

Common myths

• Myth: You must have cysts on your ovaries to have PCOS. Fact: Ovarian appearance is just one possible criterion, and the “cysts” are follicles.
• Myth: Only overweight women get PCOS. Fact: Many women with PCOS are of healthy weight.
• Myth: Women with PCOS cannot get pregnant. Fact: Most can, sometimes with treatment.
• Myth: The pill cures PCOS. Fact: It manages symptoms but does not cure the condition.
• Myth: PCOS goes away after menopause. Fact: Metabolic risks continue.

Living with PCOS: a practical plan

Track your cycle

Use a calendar or app to record the first day of each period, how heavy it is and how long it lasts. This helps you and your healthcare provider see patterns, decide on treatment and spot problems such as very long gaps or heavy, prolonged bleeding.

Build an eating pattern you can keep

Many women with PCOS feel pressure to follow extreme diets. The evidence suggests that the best approach is one you can sustain. Focus on regular meals built around vegetables, protein and high-fibre carbohydrates, limit sugary drinks and snacks, and avoid long periods of very restrictive eating, which can trigger binge eating. A dietitian with PCOS experience can help you create a plan that fits your culture, budget and preferences.

Move in ways you enjoy

Both aerobic exercise and strength training improve insulin sensitivity. Strength training builds muscle, which acts like a sponge for blood sugar. Brisk walking, dancing, cycling, swimming, home workouts and team sports all count. Consistency matters more than intensity.

Protect your sleep

Women with PCOS are more likely to have sleep problems, including obstructive sleep apnoea, particularly if they have excess weight. Snoring, gasping at night and daytime sleepiness should be checked. Good sleep supports appetite control, mood and insulin sensitivity.

Look after your mental health

Be kind to yourself. PCOS symptoms can feel visible and personal, and comments from others about weight, skin or fertility can hurt. Speak to your healthcare provider if you are feeling low, anxious or struggling with eating. Many women find online and in-person support groups help them feel less alone.

PCOS and relationships

PCOS can affect relationships, especially when fertility is a concern or symptoms affect confidence and sexual wellbeing. Open conversations with your partner about how you feel, what PCOS means and what support you need can strengthen your relationship. Couples counselling or fertility counselling can help when trying to conceive becomes stressful. Remember that PCOS is a medical condition, not a personal failing, and it does not define your worth.

PCOS and work

Symptoms such as heavy or unpredictable bleeding, fatigue, low mood and frequent appointments, particularly during fertility treatment, can affect work. You are not obliged to tell your employer, but some women find that explaining their needs leads to helpful adjustments, such as flexible hours for appointments or easy access to toilets. Occupational health services can advise confidentially.

Research and the future

Research into PCOS is growing, including studies into its genetic causes, the role of the gut microbiome, new medicines that target insulin and androgen pathways, and better ways to diagnose it in teenagers. International efforts are under way to improve awareness, reduce diagnostic delays and ensure that women in every country can access evidence-based care. The 2023 international guideline is due to be updated as new evidence emerges.

Signs that need prompt attention

• Very heavy bleeding, soaking a pad or tampon every hour, or bleeding lasting longer than ten days
• No period for more than three months (after ruling out pregnancy)
• Rapidly worsening hair growth, deepening voice or increased muscle bulk, which can suggest other, rarer hormone conditions
• Symptoms of diabetes, such as excessive thirst, frequent urination and unexplained tiredness
• Severe pelvic pain, particularly during fertility treatment
• Persistent low mood, anxiety, disordered eating or thoughts of self-harm

How PCOS care should look

Good PCOS care is long-term and covers the whole person. You should expect a clear explanation of the diagnosis, a personalised plan based on your priorities (whether that is regular periods, clearer skin, fertility or long-term health), regular checks of blood pressure, weight, blood sugar and mood, and referral to specialists such as dietitians, dermatologists, psychologists or fertility services when needed. The international guideline also emphasises shared decision-making: your priorities should shape your treatment, and you should be given evidence-based information to make informed choices.

PCOS awareness

September is recognised as PCOS Awareness Month in many countries. Awareness campaigns aim to reduce the long delays many women experience before diagnosis, often several years and multiple healthcare visits, and to challenge the stigma attached to symptoms such as excess hair and infertility. Sharing reliable information with friends and family can help others recognise the signs earlier.

Frequently asked questions

Can PCOS be cured?

There is no cure, but symptoms can be well managed and long-term risks reduced.

Is inositol helpful?

Inositol supplements are popular. The 2023 guideline found limited evidence and considers them an experimental option; discuss with your healthcare provider.

Can I have PCOS with regular periods?

Yes, if you have signs of high androgens and polycystic ovaries or raised AMH, although it is less common.

Does PCOS cause weight gain?

Insulin resistance and hormonal changes can make weight gain easier and weight loss harder, but weight management is still possible with support.

Should I stop the pill to see if I have PCOS?

Hormone tests are most accurate off the pill, but talk to your healthcare provider about how and when to test, and use other contraception if needed.

But will anything really make a difference?

Yes. A clear diagnosis lets you understand your body, plan for pregnancy, protect your long-term health and get effective treatment for symptoms that affect your confidence. Small, sustained changes in activity and eating, combined with the right medical care, can transform how you feel. Do not accept being told to simply “lose weight and come back later”.

Related: PCOS signs and pregnancy · Metformin explained · AMH and FSH fertility tests · Hair loss in women

Sources: World Health Organization (PCOS fact sheet), International Evidence-based Guideline for the Assessment and Management of Polycystic Ovary Syndrome (2023, Monash University and partners), American College of Obstetricians and Gynecologists, Royal College of Obstetricians and Gynaecologists, Endocrine Society.