[CG] Polycystic Ovarian Syndrome, investigation and management


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Polycystic Ovary Syndrome (PCOS) is a common condition affecting 6-7% of the female population. The key clinical features are hyperandrogenism (hirsutism, acne, male-pattern hair loss) and menstrual irregularity with associated anovulatory infertility. 40-50% of women with PCOS are overweight. Insulin resistance is seen in 10-15% of slim and 20-40% of obese women with the disorder and all women with PCOS are at an increased risk of developing type 2 diabetes.

This guideline excludes the management of associated subfertility.  For these women, referral should be made to Assisted Conception Services (ACS).


PCOS can be diagnosed when 2 out of the following 3 diagnostic criteria are present (Rotterdam consensus)

  • Oligo- or amenorrhoea
  • Clinical and/or biochemical signs of hyperandrogenism (elevated androstendione)
  • Polycystic ovaries on TVS (ovary containing 12 or more peripheral follicles measuring 2-9mm )


A full medical history is required including smear history. Also include a menstrual history and fertility requirements


  • Speculum and bimanual pelvic examination
  • Also look for: hirsutism, acne, male-pattern hair loss
  • BMI and BP if not previously recorded

Baseline blood tests to be performed

  • Thyroid function tests
  • Serum prolactin
  • Androgen profile (to exclude other causes of clinical hyperandrogenism e.g. late-onset CAH) .This is a new assay carried out in GGC and replaces FAI and SHBG. A raised androstenedione is a more sensitive indicator of PCOS than calculation of FAI. 
  • LH/FSH/oestradiol (a raised LH:FSH ratio is no longer a diagnostic criterion however LH/FSH/oestradiol should be checked to exclude other causes of oligomenorrhoea)

If there is clinical suspicion of Cushing Syndrome referral should be made to an endocrinologist


TVS to assess ovarian morphology and endometrial appearance should be considered but is not essential.


Women diagnosed with PCOS should be informed of the possible long-term risks to health associated with the condition (Type 2 DM is commoner irrespective of BMI) and the positive effects of lifestyle changes emphasised.

Women should be counselled that there is no evidence that PCOS by itself causes weight gain or makes weight loss more difficult.

Lifestyle changes through diet and exercise are first line treatment for PCOS associated with obesity- weight loss has a significant effect on lowering serum androgen levels, restoring regular menses and increasing the number of ovulatory cycles.

Referral to local weight management service should be offered.

HbA1c should be checked in women diagnosed with PCOS who have BMI >25 or BMI <25 with additional risk factors ( > 40 years, past history of gestational diabetes, family history of type 2 DM ). While the current RCOG guideline suggests 75G oral GTT local advice is to use HbA1c as it is more clinically useful.

Insulin sensitising agents including METFORMIN should NOT be prescribed as first-line therapy.
There is currently no evidence that they confer any long term benefit. They should only be prescribed in the context of a specialist endocrine clinic

Cardiovascular disease risk should be assessed by assessing individual risk factors (obesity, lack of physical activity, smoking, FH DM Type 2, hypertension etc).

Oligomenorrhoiec women ( > 3 months between menses)  should be offered gestogenic endometrial protection to reduce the risk of developing endometrial hyperplasia- at a minimum 12days of oral gestogen (medroxyprogesterone acetate 20mg/day or norethisterone 10mg/day) every 3-4 months.

Combined hormonal contraception increases SHBG and can be useful. Gestagenic preparations (levonorgestrel intra-uterine system, etonogestrel subdermal implant and depo medroxyprogesterone acetate) provide effective endometrial protection-these preparations often induce amenorrhoea but induction of withdrawal bleeding in this situation is not required.

Cosmetic measures (laser, bleaching, threading, waxing etc.) disguise hirsutism and topically applied eflornithine (Vaniqa®) is of some benefit in reducing facial hair growth and should be used for 3 months prior to referral for laser treatment of hirsutism.*

Psychological issues should be considered. Women with PCOS are at increased risk of psychological and behavioural disorders. If these are present further assessment and management by appropriately trained professionals is indicated.

Ovarian electrocautery should be considered for selected anovulatory patients, especially those with normal BMI, as an alternative to ovulation induction


* Women with PCOS and facial hirsutism may be eligible for NHS laser treatment. The referral form / criteria are available on staffnet under clinical info / referral guidance directory / plastic surgery.

Long Term Consequences

Sleep apnoea is more common in PCOS – a history of snoring and daytime fatigue should prompt referral for investigations. CPAP therapy improves insulin sensitivity in affected women.

Cardiovascular risk increase is related to obesity and hypertension rather than PCOS itself.

Women with PCOS are at an increased risk of endometrial hyperplasia and malignancy secondary to prolonged anovulation and oligo- and amenorrhoea. Endometrial protection should be provided as detailed above.

Patient Information Resources

Last reviewed: 01 October 2017

Next review: 30 September 2022

Author(s): Claire Higgins

Approved By: Dr R Jamieson, Clinical Director