Investigations are summarised below with further discussion of some points in Clinical Features:

There is no single diagnostic test for PCOS. It is important to ensure the patient is not taking the oral contraceptive pill (OCP) for at least three months before hormone testing, with accompanying contraceptive advice.

Key investigations include testosterone, SHBG and free androgen index or calculated free testosterone, or calculated bioavailable testosterone,

Luteal phase (day 22-24) progesterone²³ can be used to assess ovulation in women with hirsutism who report regular menstrual cycles.

Other diagnoses need to be excluded by testing prolactin, TSH and serum 17-hydroxyprogesterone.Late onset congenital adrenal hyperplasia should be excluded before PCOS is diagnosed²⁴. Serum 17-hydroxyprogesterone should be measured in the follicular phase if possible.

If clinical examination is suggestive, a screen for Cushing’s syndrome should be performed. Tests for dehydroepiandrosterone-sulphate (DHEAS) and androstenedionecould be considered as second-line investigations to exclude other causes of hyperandrogenism in PCOS²⁴. DHEAS may be mildly raised in PCOS but markedly raised in the setting of androgen secreting tumours, however a clinical history of rapid virilisation is more useful²³. Androstenediones may be mildly elevated in PCOS but marked elevations are more indicative of non-classical adrenal hyperplasia²⁴.

Optional investigations include a pelvic ultrasoundfor ovarian morphology and endometrial thickness. The recent PCOS Evidence Based Guidelines state that the role of pelvic ultrasound in the diagnosis of adolescents is unclear. Follicle counts are high in this age group thus there is a high prevalence of polycystic ovaries on ultrasound and over-diagnosis needs to be avoided. Given the apparent lack of specificity of polycystic ovaries on ultrasound in adolescents, generally, ultrasound should not be recommended first-line in this age group. for the diagnosis of PCOS pending further research.If pelvic ultrasounds are to be ordered in adolescents, the result should be interpreted with caution. In addition, vaginal ultrasounds are inappropriate in adolescents who have not been sexually active²⁴.

A cardiometabolic risk assessment is recommended. A number of recommendations have been made in the 2011 PCOS evidence-based guideline²⁴. BMI should be measured at every visit. A lipid profile should be performed every two years if normal or annually if abnormal or BMI is elevated. This includes total cholesterol (aim <4 mmol/L), low density lipoprotein cholesterol (LDL-C) (aim < 3.4mmol/L or 1.0 mmol/L) and triglycerides (aim <1.7 mmol/L).  Blood pressure should be measured annually in women with BMI < 25 kg/m² and at each visit if BMI > 25 kg/m^2. A daytime bloodpressure of 135/85 mmHg is recommended in those at high risk of diabetes²⁴.

An OGTT is appropriate in all women at diagnosis. If results are normal, they should be rescreened approximately every two years or annually if BMI > 30 kg/m^2, , history of gestational diabetes is present, high risk ethnic group or family history of diabetes is present²⁴. If results show that a patient has impaired glucose tolerance (IGT), she should be screened annually for diabetes. IGT should be treated intensively with lifestyle modifications⁵⁰. A fasting glucose level does not suffice in excluding either IGT or diabetes in these women, as noted previously. Insulin levels are not recommended in clinical practice because of assay variability and inaccuracy. Metabolic syndrome and abnormal glucose metabolism best reflect insulin resistance in this population.

Screening for depression, anxiety, body image, disordered eating and psychosexual dysfunctionshould be performed in women with PCOS²⁴. Specific screening methods are documented in the 2011 Evidence-Based Guideline.

This article first appeared in Australian Doctor - How to treat on 29 August 2008 and has been reproduced here with permission.

 Australian Doctor - How to treat: Polycystic ovary syndrome 437.44 Kb

Content updated 7 September 2011