PCOS is a common condition, with prevalence estimated anywhere between 2% and 30% depending on the criteria used.

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of reproductive age. There is a wide clinical spectrum, with some women experiencing relatively mild symptoms whilst others suffer with debilitating effects.

Clinical features are those of hyperandrogenism (acne, oligomenorrhoea and hirsutism) and anovulatory infertility.


The aetiology of PCOS remains poorly understood.

Hypothalamic-pituitary-ovarian dysfunction and insulin resistance commonly appear to play key roles.

Insulin resistance

Insulin resistance and resulting hyperinsulinaemia are common. This leads to a reduction in sex hormone-binding globulin (SHBG), leading to increased biologically active free testosterone. 

Excess androgens result in anovulation and menstrual irregularity.

Hormonal imbalance

Luteinising hormone is elevated in around 40% of women, associated with increased production in the anterior pituitary.

Excess androgens are produced by theca cells (in the ovary) in response to the abnormal LH/FSH ratio or hyperinsulinaemia

Clinical features

Features are those of androgen excess and menstrual irregularity. 


  • Oligo/amenorrhoea
  • Infertility/sub-fertility
  • Acne
  • Hirsutism
  • Obesity
  • Sleep apnea
  • Anxiety/depression


  • Hirsutism
  • Obesity
  • Acanthosis nigricans

Differential diagnosis

It is essential to exclude other causes of similar symptoms.

  • Cushing’s syndrome
  • Primary hypothyroidism
  • Androgen-secreting tumour 
  • Non-classic congenital adrenal hyperplasia 
  • Premature ovarian failure


The RCOG advise the Rotterdam criteria be used to make a diagnosis of PCOS.

PCOS is indicated by the presence of two of the following three points:

  1. Polycystic ovaries (12 or more follicles (2-9mm) on one ovary or increased ovarian volume (>10cm3))
  2. Oligo-anovulation or anovulation
  3. Clinical and/or biochemical signs of hyperandrogenism 


PCOS is a chronic condition with long-term implications for a women’s health.

Each patient should receive counselling from a medical professional. The nature of PCOS and potential implications on fertility and cardiovascular health should be explained.

Essentially, the importance of optimising modifiable risk factors such as weight and diet should be highlighted. Though women should be aware PCOS itself may make weight loss challenging. 

Support groups exist and may be a source of comfort and information. See further reading section below for more information.

Cancer and PCOS

There appears to be an increased risk of endometrial cancer in patients with PCOS.

The combination of oligo/amenorrhoea and pre-menopausal oestrogen levels are thought to lead to endometrial hyperplasia and endometrial carcinoma. 

It is recommended that in patients with oligo/amenorrhoea, withdrawal bleed is induced every 3-4 months. TV USS is considered in patients with abnormal uterine bleeding or absent withdrawal bleeds.


Management of PCOS is complex and may require ongoing long-term care.

Managing clinical features of PCOS

1. Oligo/amenorrhoea

In adult patients with oligo/amenorrhoea for 3 months or longer NICE CKS advise a cyclical progestogen to induce a withdrawal bleed and referral for a TV USS (any abnormalities will require further investigation).

Induction of regular withdrawal bleeds (at least every 3-4 months) and prevention of endometrial thickening is advised. Options include cyclical progestogen, combined oral contraceptive and levonorgestrel-releasing intrauterine system. 

Some patients may be unwilling to take any hormonal therapy. Ensure they are aware of the potential health risk, refer to specialist care and organise regular TV USS.

In adolescent patients consider the combined oral contraceptive to manage hyperandrogenism symptoms and menstrual irregularity.

2. Hirsutism

Weight loss (if overweight) may help reduce hyperandrogenism - though this can be challenging. The combined oral contraceptive may be of benefit.  

If the women wants to consider hair removal techniques these should be discussed.

3. Acne

The combined oral contraceptive should be considered first-line therapy. Weight loss should be encouraged if relevant.

Consider other therapies as part of normal acne management.

4. Infertility

Advise on weight loss (if overweight) and smoking cessation should be given. Other causes of infertility should be excluded.


A healthy lifestyle is recommended. In patients who are overweight, support and advice to lose weight should be given. 

A healthy diet and regular exercise should be advised. Referral to dietician can be considered.

Psychological health

Anxiety and depression are common and should be screened for. Other issues such as psychosexual difficulties and eating disorders may occur and require specialist referral. 


Women planning pregnancy should have an oral glucose tolerance test. If already pregnant it should be conducted prior to 20 weeks.

Pregnant women should have an oral glucose tolerance test again at 24-28 weeks.

In particular metformin should be avoided in pregnancy.


PCOS may result in a number of complications that should be anticipated or screened for.

  • T2DM
  • Gestational diabetes
  • Cardiovascular disease
  • Sleep apnea
  • Depression/anxiety

Further reading

  • RCOG: Long-term Consequences of Polycystic Ovary Syndrome, Green-top Guideline No. 33, Nov 2014.
  • Verity: A UK based charity that provides support to those with PCOS.

Pulsenotes uses cookies. By continuing to browse and use this application, you are agreeing to our use of cookies. Find out more here.