What Is PCOS in Women? Symptoms and Treatment

Polycystic ovary syndrome (PCOS) in women is one of the most common hormonal conditions affecting those of reproductive age, with the NHS estimating it affects around 1 in 10 women in the UK. It involves an imbalance of reproductive hormones, particularly elevated androgens, which can disrupt ovulation and cause a wide range of symptoms including irregular periods, excess hair growth, acne and fertility difficulties. PCOS also carries longer-term metabolic risks, including a higher likelihood of developing type 2 diabetes and cardiovascular disease. Understanding what PCOS is, how it is diagnosed and what treatments are available is essential for effective management.

What exactly is PCOS and how does it affect women?

PCOS is a common hormonal condition affecting around 1 in 10 UK women of reproductive age, characterised by elevated androgens, disrupted ovulation and associated long-term metabolic risks including type 2 diabetes and cardiovascular disease.

Polycystic ovary syndrome (PCOS) is a common hormonal condition that affects the ovaries and can disrupt a woman's reproductive, metabolic and psychological health across her lifetime. The name refers to the appearance of the ovaries on ultrasound, where multiple small follicles (sometimes described as cysts, though they are not true cysts) can be seen arranged around the outer edge of each ovary. PCOS is one of the most prevalent endocrine disorders in women of reproductive age; the NHS estimates it affects around 1 in 10 women in the UK.^[1][6]

The condition involves an imbalance of reproductive hormones, particularly elevated levels of androgens (often called male hormones, though women produce them too) and disruption to the normal pattern of ovulation. This hormonal imbalance means that eggs may not develop or be released regularly, which can affect fertility and cause a range of other symptoms throughout the body.

PCOS does not affect all women in the same way. Some women experience mild symptoms that have little impact on daily life, while others face significant challenges including difficulty conceiving, persistent skin problems and long-term metabolic complications. Over time, chronic anovulation (absent or infrequent ovulation) can increase the risk of endometrial hyperplasia, and the condition is also associated with a higher risk of type 2 diabetes, dyslipidaemia and cardiovascular disease.^[10][11] These longer-term risks are part of why monitoring and cycle control matter, even when immediate symptoms are mild.

Because PCOS is a syndrome rather than a single disease, it is defined by a cluster of features rather than one specific cause or test result. Understanding this complexity is important for both diagnosis and management, and women are encouraged to discuss their individual pattern of symptoms with their GP.

What are the most common signs and symptoms of PCOS?

The most common symptoms of PCOS are irregular or absent periods, hirsutism, acne, scalp hair thinning and fertility difficulties, all driven primarily by elevated androgen levels and disrupted ovulation.

Irregular or absent periods are among the most frequently reported symptoms of PCOS, occurring because the hormonal imbalance disrupts the normal monthly cycle of ovulation. When ovulation does not happen regularly, the lining of the uterus may not shed as expected, leading to infrequent periods (oligomenorrhoea) or periods stopping altogether (amenorrhoea). Some women have fewer than eight periods per year.

Elevated androgen levels drive several other common features of the condition:

• Excess hair growth (hirsutism): Unwanted hair on the face, chest, back or abdomen, following a typically male pattern.

• Acne: Persistent or adult-onset acne, particularly along the jawline and chin.

• Scalp hair thinning: Some women notice hair loss or thinning at the crown, similar to male-pattern baldness.

• Oily skin: Increased sebum production linked to androgen excess.

Weight gain and difficulty losing weight are also commonly reported, and many women with PCOS have insulin resistance, meaning the body's cells do not respond efficiently to insulin. This can contribute to weight gain around the abdomen and raises the longer-term risk of type 2 diabetes.

Fertility difficulties are another significant concern, as irregular ovulation makes it harder to conceive naturally. Additionally, PCOS is associated with a higher risk of low mood and anxiety, and the psychological impact of symptoms such as unwanted hair growth or weight changes should not be underestimated.

When to seek urgent review: Women who notice rapid onset of virilising features (such as a deepening voice, marked clitoral enlargement or very sudden, severe hair growth), or who develop new androgenic symptoms after the menopause, should seek prompt medical assessment, as these presentations may indicate a cause other than PCOS that requires urgent investigation.

Women who have fewer than four periods per year should also discuss this with their GP, as infrequent shedding of the uterine lining can increase the risk of endometrial hyperplasia and strategies to protect the endometrium may be needed.^[10][11]

Women experiencing any combination of the more typical symptoms described above are encouraged to speak to their GP, as early assessment can help prevent longer-term complications.

How is PCOS diagnosed on the NHS?

PCOS is diagnosed using the Rotterdam criteria, requiring at least two of three features: irregular ovulation, elevated androgens and polycystic-appearing ovaries on ultrasound, supported by blood tests to exclude other conditions.

PCOS is diagnosed on the NHS using the Rotterdam criteria, which require at least two of the following three features to be present: irregular or infrequent ovulation, clinical or biochemical signs of elevated androgens, and polycystic-appearing ovaries on ultrasound. No single test confirms PCOS on its own, so diagnosis involves a combination of clinical assessment, blood tests and, in some cases, imaging.

A GP will typically begin by taking a detailed history of menstrual patterns, symptoms and any relevant family history. A pregnancy test is usually performed where periods are absent. Blood tests are used to measure hormone levels and to exclude other conditions; these commonly include:

• Testosterone and other androgens: To identify biochemical hyperandrogenism.

• Prolactin and thyroid-stimulating hormone (TSH): To exclude hyperprolactinaemia and thyroid disorders, which can cause similar symptoms.

• 17-hydroxyprogesterone: To exclude non-classic congenital adrenal hyperplasia, particularly where androgen excess is marked.

• HbA1c and/or fasting plasma glucose: To screen for impaired glucose regulation and type 2 diabetes risk, in line with UK practice. An oral glucose tolerance test (OGTT) may be arranged in selected cases. Routine measurement of fasting insulin is not recommended in UK clinical practice.^[3]

Note on LH and FSH: luteinising hormone (LH) and follicle-stimulating hormone (FSH) may be measured to help exclude other causes of cycle disturbance (such as premature ovarian insufficiency), but the LH to FSH ratio is not a diagnostic criterion for PCOS under UK guidance and should not be relied upon for diagnosis.

A pelvic ultrasound may be arranged to examine the ovaries, though NICE guidance notes that a polycystic appearance on ultrasound alone is not sufficient for diagnosis, and ultrasound is not always necessary if the other two criteria are already met. In adolescents, pelvic ultrasound is generally avoided within approximately eight years of the first period, as polycystic-appearing ovaries are common in this age group and do not reliably indicate PCOS; in younger people, diagnosis should be based on persistent menstrual irregularity combined with clinical or biochemical hyperandrogenism.^[17][18]

Baseline cardiometabolic assessment, including blood pressure and a fasting lipid profile, is also recommended at diagnosis, with ongoing monitoring at intervals guided by individual risk.

Other conditions that can mimic PCOS, such as thyroid disorders, hyperprolactinaemia and congenital adrenal hyperplasia, must be excluded before a diagnosis is confirmed. Women who are concerned about their symptoms should contact their GP in the first instance. If symptoms are complex or fertility is affected, referral to a gynaecologist or endocrinologist may be appropriate.

What causes PCOS and who is most at risk?

PCOS results from a combination of genetic, hormonal and environmental factors; insulin resistance and a family history of PCOS or type 2 diabetes are among the strongest risk factors.

The exact cause of PCOS is not fully understood, but the condition is thought to result from a combination of genetic, hormonal and environmental factors rather than a single identifiable trigger. Research consistently shows that PCOS runs in families, suggesting a significant genetic component. Women who have a mother, sister or other close female relative with PCOS are at greater risk of developing the condition themselves.

Insulin resistance plays a central role in many cases. When cells do not respond normally to insulin, the pancreas produces more of it to compensate. High insulin levels can stimulate the ovaries to produce excess androgens, which in turn disrupt ovulation and drive many of the characteristic symptoms.^[15][16] This link between insulin resistance and PCOS helps explain why the condition is more common in women with obesity, though it is important to note that PCOS also affects women of a healthy weight.

Other factors associated with increased risk include:

• Family history of type 2 diabetes: Reflecting shared insulin resistance pathways.

• Ethnicity: Some evidence suggests that women of South Asian or Black ethnicity may have a higher prevalence of PCOS or more pronounced metabolic features, though the evidence base is heterogeneous and further UK-specific research is ongoing.^[19][20] Women from these groups may benefit from earlier cardiometabolic assessment.

• Puberty: PCOS often first becomes apparent around the time of the first menstrual periods, when hormonal changes are most pronounced.

Low-grade chronic inflammation has also been identified in some women with PCOS and may contribute to androgen overproduction, though the precise role of inflammation is still being investigated and should not be overstated.

While lifestyle factors such as diet and physical activity can influence the severity of symptoms, they are not considered a direct cause of the condition. PCOS is not caused by anything a woman has done or failed to do.

What treatments and lifestyle changes can help manage PCOS?

PCOS is managed through lifestyle changes, medications such as the combined oral contraceptive pill or metformin, and specialist treatments for fertility or hirsutism; there is no cure, but symptoms and long-term risks can be effectively controlled.

PCOS has no cure, but a range of treatments and lifestyle strategies can effectively manage symptoms and reduce the risk of long-term complications such as type 2 diabetes and cardiovascular disease. Treatment is tailored to each woman's individual symptoms and priorities, including whether she is trying to conceive.

Lifestyle changes are recommended as a first-line approach by NICE for women with PCOS who are overweight.^[2][3] Evidence from the international evidence-based PCOS guideline (Monash/ESHRE/ASRM) suggests that even a modest reduction in body weight of around 5 to 10 per cent can restore more regular ovulation, improve insulin sensitivity and reduce androgen levels.^[7] A balanced diet that limits refined carbohydrates and regular physical activity are both beneficial across all BMI groups, not only for those who are overweight.

Medications used in PCOS management include:

• Combined oral contraceptive pill (COCP): Regulates periods, reduces androgen levels and can improve acne and hirsutism in women not trying to conceive. The COCP also provides endometrial protection for women with infrequent bleeds. Cyclic progestogens or a levonorgestrel-releasing intrauterine system (LNG-IUS) are alternative strategies for endometrial protection where the COCP is not suitable; a GP or specialist can advise on the most appropriate option.

• Metformin: An insulin-sensitising medicine that can help regulate periods and reduce metabolic risk, particularly in women with insulin resistance or impaired glucose tolerance. It is used off-label for PCOS in the UK and is typically initiated in line with local policies or following specialist advice.^[4][24]

• Letrozole or clomifene: Used to stimulate ovulation in women trying to conceive, under specialist supervision. The international PCOS guideline recommends letrozole as the preferred first-line agent for ovulation induction; both are used off-label for this purpose in the UK and should only be prescribed by a specialist.^[21][22]

• Anti-androgens: Medicines such as spironolactone or finasteride may be considered by a specialist for women with troublesome hirsutism or acne that has not responded to other treatments. These medicines must not be taken during pregnancy and require effective contraception; monitoring requirements apply. They are not routinely prescribed in primary care for PCOS.

• Topical treatments for facial hair: Eflornithine cream is licensed in the UK for the treatment of unwanted facial hair in women and may be prescribed by a GP or specialist. Availability can vary; a prescriber can advise on current options.

For women seeking support with weight management as part of their PCOS care, a GP can advise on NHS pathways and referral options. Bolt Pharmacy is a GPhC-registered UK online pharmacy offering online weight-management consultations, with prescriber review and pharmacist support, which may be relevant for women whose PCOS is complicated by weight-related metabolic concerns. Any prescription medicine would only be provided following a clinical consultation and where a prescriber considers it appropriate.

Ongoing cardiometabolic monitoring is recommended after diagnosis, including periodic checks of blood glucose (HbA1c or fasting glucose, with OGTT where indicated), blood pressure and lipid levels, at intervals guided by individual risk and local guidance.

Psychological support, including cognitive behavioural therapy, may also be beneficial given the impact PCOS can have on mood and self-esteem. Women should discuss all available options with their GP or specialist to develop a management plan suited to their needs.

Scientific References

1. Polycystic ovary syndrome (PCOS).
2. Polycystic ovary syndrome: metformin in women not planning pregnancy (ESUOM6) – patient information.
3. Polycystic ovary syndrome – Treatment summaries.
4. Polycystic ovary syndrome: metformin in women not planning pregnancy (ESUOM6) – full resource.
5. Polycystic Ovary Syndrome and Risk of Type 2 Diabetes, Coronary Heart Disease, and Stroke.
6. Rising Incidence, Health Resource Utilization, and Costs of Polycystic Ovary Syndrome.
7. Lifestyle interventions for cardiometabolic health in women with polycystic ovary syndrome: a systematic review and network meta-analysis.
8. Recent advances in polyendocrine metabolic ovarian syndrome (PMOS), formerly polycystic ovary syndrome, with emphasis on endocrine and metabolic dysfunction and cardiovascular risk.
9. Association of polycystic ovary syndrome with metabolic syndrome and its components in adolescents: a systematic review and meta-analysis.
10. Screening for endometrial hyperplasia and endometrial cancer in premenopausal women with PCOS.
11. Gynecologic Cancers: Endometrial Cancer.
12. Fertility Challenges Facing Women with Early-Stage Endometrial Cancer.
13. Using machine learning to discriminate non-classical 21-hydroxylase deficiency from polycystic ovary syndrome: an external validation study.
14. Steroid Screening Tools Differentiating Nonclassical Congenital Adrenal Hyperplasia and Polycystic Ovary Syndrome.
15. Insulin signaling in PCOS/PMOS: molecular insights and clinical implications.
16. Physical activity, sedentary behavior, and metabolic-reproductive health in women with PMOS (PCOS): a narrative review of mechanisms, clinical evidence, and individualized intervention strategies.
17. Update on diagnosis of polycystic ovary syndrome during adolescence.
18. The value of anti-Mullerian hormone for diagnosing polycystic ovary syndrome in adolescents: a case-control study based on an epidemiological survey.
19. Influence of ethnicity on different aspects of polycystic ovary syndrome: a systematic review.
20. The PCOS Phenotype in Unselected Populations study: ethnic variation in population-based normative cut-offs for defining hirsutism.
21. Phenotype-specific efficacy of letrozole versus clomiphene citrate in polycystic ovary syndrome: a prospective cohort study.
22. Comparative Outcomes of Letrozole Versus Clomiphene Citrate for Ovulation Induction in Patients With PCOS: Systematic Review and Meta-Analysis.
23. Combined Letrozole and Clomiphene Citrate Versus Letrozole Alone in Ovulation Induction for Polycystic Ovarian Syndrome Patients: A Systematic Review and Meta-analysis of Randomized Controlled Trials.
24. Metformin Tillomed SR 750 mg Prolonged-release Tablet – Summary of Product Characteristics.

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