Polycystic ovarian syndrome

The diagnosis of PCOS requires confirmation of ovarian dysfunction: irregular or anovulatory cycles, or polycystic morphology on scanning; and androgen excess: either clinical or biochemical.

Diagnosis of PCOS should only be considered in patients after ruling out other conditions

From a practical perspective the following conditions should be excluded before confirming a diagnosis of PCOS. Thyroid dysfunction, prolactinoma, congenital adrenal hyperplasia, virilising tumours (ovarian or adrenal) and Cushing’s (diagnosis usually excluded clinically).

In practise, the minimum assessment required before a diagnosis of PCOS can be considered likely are a normal prolactin, normal TSH and a testosterone <3.5nmol/l. In the presence of these results, no further investigations may be necessary in some cases. 

Current diagnostic criteria require the presence of both hyperandrogenism and ovarian dysfunction

Latest guidelines from the Androgen excess society and PCOS society have clarified the diagnosis of PCOS, requiring both hyperandrogenism and ovulatory dysfunction.

Evidence of hyperandrogenism may be either clinical, for example hirsuitism or acne, or biochemical such as elevated testosterone.

Evidence of ovulatory dysfunction may also be either clinical, for example oligomenorrhoea or anovulatory cycles confirmed with a day 21 progesterone, or as evidenced by polycystic morphology on ultrasound scanning.

These criteria replace and simplify the previous 'Rotterdam criteria' which required at least two out of three of: hyperandrogenism (either biochemical or clinical), or anovulation (as evidenced by oligomenorrhoea or infertility), or polycystic morphology on ultrasound scan.

Other diagnoses to be considered in the differential of hirsuitism and irregular menses

Idiopathic hirsuitism, hirsuitism and hyperandrogenism, congenital adrenal hyperplasia, Cushing’s syndrome, virilising tumours, prolactinoma, thyroid dysfunction or the HAIRAN syndrome may all present with similar features to PCOS.

If the clinical picture is consistant with PCOS but the testosterone is elevated, the simplest way to exclude a virilising tumour is to perform a low dose dexamethasone suppression test. If there is a strong suspicion of CAH, and the patient is seeking fertility, a 17OHprogesterone should be performed with a synacthen test if the result is elevated, though this is not mandatory in all patients with hirsuitism.

Management of confirmed PCOS should be tailored to the individual's primary complaint


Diet and lifestyle advice are essential for all patients with PCOS. Management of other cardiovascular risk factors should also be undertaken when indicated.

Suggest patient support groups, for example Verity website.

Consider metformin with slow dose titration, to minimise gastrointestinal side effects, or controlled release metformin if this is poorly tolerated.

Consider further management of obesity, for example with orlistat, sibutramine and bariatric surgery.


Diet and lifestyle advice are essential for all patients with PCOS. 

A combined oral contraceptive pill should be considered as any will reduce free androgen levels. For severe androgenic acne, a combined pill containing the anti-androgen cyproterone such as cocyprindiol is more effective.

Where acne is the primary clinical concern, non hormonal measures may be more appropriate, for example antibiotics or retinoic acid, and so specialist dermatology advice should be sought.


Diet and lifestyle advice are essential for all patients with PCOS. 

Warn patients that all treatments for hirsuitism tend to take at least six months and none are 100% effective.

Topical eflornithine or other topical measures may be considered first line, and are usually given in addition to metformin given for other indications.

A combined oral contraceptive pill (COCP) should also be considered and for severe hirsuitism, one containing an anti-androgen is most effective such as cocyprindiol or dianette.

An anti-androgen, for example spironolactone (dose titrate from 25 to 200mg), may be added to the COCP if no effects have been observed after at least six months. Cyproterone acetate has also been widely used although this is not licenced and requires close monitoring of liver function. Finasteride is another alternative anti-androgen for exceptional use only.

Where the COCP is contraindicated - for example in patients over 35 years, smokers, those with a history of thromboembolism, or is not tolerated with mood disturbance - anti-androgens may still be prescribed in the presence of robust contraception.

If hirstuitism is severe, for example requiring daily shaving, and there has been no response to topical and medical therapies, consider pulsed light therapy or laser hair removal.


Diet and lifestyle advice are essential for all patients with PCOS.

Metformin should also be considered to improve menstrual regularity.

The COCP will almost always restore regular withdrawal bleeds, and is generally well tolerated. Where this is contra-indicated, or not well tolerated, consider intermittent progesterone (norethisterone acetate 5mg tds 5/7) to induce endometrial shedding every three months in amenorrhoeic patients.

Reverse circadian prednisolone was historically widely used and can be highly effective at restoring menses. However, this requires thorough education and counselling of the patient regarding likely side effects, and is now seldom used.


Diet and lifestyle advice are essential for all patients with PCOS. 

Patients whose primary concern is fertility should be reviewed in a formal fertility clinic for counselling, and to investigate both partners for other causes.

Metformin should be considered to improve menstrual irregularity, though has not been proven to improve pregnancy rates in recent controlled studies.

Reverse circadian prednisolone may also be considered for anovulatory cycles though is no longer widely used.

If the patient remains anovulatory, clomiphene acetate should be considered under gynaecological review and with follicular tracking.