Polycystic ovary syndrome and the differential diagnosis of hyperandrogenism

Key content The presence of clinical or biochemical evidence of hyperandrogenism is a defining feature of polycystic ovary syndrome (PCOS). As the criteria for diagnosing PCOS becomes more inclusive, there is an increased risk of misdiagnosing women with other causes of hyperandrogenism. Biochemical testing for serum testosterone concentrations in women has important limitations. Patients with concerning features should be investigated for other causes of hyperandrogenism. Learning objectives To review the different criteria for diagnosing PCOS and the repercussions for disease prevalence. To learn about the differential diagnosis of hyperandrogenism. To learn about the limitations of biochemical testing for testosterone in women. Ethical issues Hyperandrogenism causing hirsutism and virilisation can have significant effects on physical and psychological wellbeing. Misdiagnosis can delay appropriate treatment and may affect future fertility.