Polycystic ovary syndrome (PCOS)

No single test. Polycystic kidneys are a common incidental finding at USS, so not sufficient for diagnosis.  Also operator dependent esp teens.

  • Hirsutism (even male pattern baldness), But NOT virilisation (eg clitoromegaly, voice changes, musculature).
  • acne (moderate to severe),
  • irregular periods.  Can be amenorrhoeic, dysfunctional uterine bleeding, infertility but 20% have normal cycle.
  • Obesity (35-50%, not all),
  • Acanthosis nigricans.

Insulin resistance is associated, and obviously presents the most important long term risk. Acanthosis nigricans is highly associated with insulin resistance, family history of type 2 or gestational diabetes a clue.

Differential includes pregnancy, hypothyroidism, hyperprolactinaemia (mild hyperprolactinaemia commonly seen in PCOS, transient), late onset Congenital Adrenal Hyperplasia (CAH), ovarian/adrenal tumour, Cushing syndrome.


  • LH/FSH – ratio often high (3:1 or more) but inconsistent so not considered diagnostic
  • Testosterone can be high (up to 4.8) – if higher, suggests alternative diagnosis
  • Free androgen index (=testosterone x100/SHBG) can be high but our lab only calculates for adults – reference range of up to 7
  • SHBG – low in PCOS (and in obesity, hypothyroidism, hyperprolactinaemia). Plus marker of insulin resistance),
  • Prolactin, 17OH Progesterone for differential
  • Fasting glucose/insulin ratio (under 4.5=insulin resistance, up to 7 in adolescents), glucose tolerance test, lipids.

Manage symptoms (for young people hirsutism, adults infertility) and long term risk viz diabetes and cardiovascular disease.

Note that less than 4 menses per year has higher risk of endometrial cancer.


  • oral contraceptive pill (OCP) – progesterone only, or combined, or else 12 week cycles of medroxyprogesterone acetate 5mg BD followed by 1 week break – NOT contraceptive!
  • Metformin
  • Spironolactone (has anti androgen effect)
  • Plucking/shaving/electrolysis/laser, eflornithine cream
  • Clomiphene for fertility.