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Polycystic ovarian syndrome - Dr Deac Pimp

Definition

  • An androgenic syndrome caused by multiple follicles on the ovaries, a common cause of subfertility
    • Is a misnomer, as is a result of follicles NOT cysts
  • Diagnosis requires 2 of the following:
    • Elevated serum androgens OR clinical signs of hyperandrogenism
    • Polycystic ovaries as visualised on USS (at least 12 follicles of >10cm3 volume)
    • Anovulation/oligo-ovulation (clinically manifesting as amenorrhoea/oligomenorrhoea [<9 menses per year])

 

Risk factors

  • Family history of PCOS
  • Family history of diabetes
  • Valproate
  • Obesity

 

Differential diagnoses

  • Hypothyroidism/Hashimoto’s
  • Hyperprolactinaemia
  • Cushing’s
  • Acromegaly
  • Ovarian or adrenal tumour
  • Androgenising medication side-effect
  • CAH (congenital adrenal hyperplasia)

 

Epidemiology

  • Most common endocrine disorder in women
  • Very common – prevalence of 5-15% of women of reproductive age
  • 33% of women have polycystic ovaries on USS
  • Usually presents in late teens and 20s
  • Is the cause of infertility in 75% of anovulatory women

 

Aetiology

  • X-linked dominant condition, so can be passed down maternal or paternal lineage (probably)
  • Exact cause unknown
  • Obesity is likely to play a causative role, as well as a reactive one

 

Clinical features

  • Presentation is usually in late teens and 20s
  • Androgenisation:
    • Hirsuitism (60%)
    • Acne
    • Male pattern balding
    • Clitoromegaly (rare)
    • Deep voice (rare)
  • Alopecia
  • Central obesity
  • Sleep apnoea
  • Mood disturbance
  • Acanthosis nigricans (insulin resistance)
  • Amenorrhoea/oligomenorrhoea (<9 menstrual cycles per year)
  • Irregular periods
  • Subfertility/infertility (in 70-80% of patients)
  • May also present with signs/symptoms of diabetes, as these go hand in hand

 

Pathophysiology

  • Theca cells of the ovaries produce more androgens
    • Caused by hyperinsulinaemia OR
    • Increased LH
  • Insulin resistance leads to hyperinsulinaemia
  • Weight gain increases hyperinsulinaemia, which results in:
    • More androgrens – propagating a cycle
    • Reduced production of sex-binding globulin by the liver, so free testosterone levels may be raised, even if total levels are normal
  • Increased LH production from anterior pituitary (in approx. 40%)

 

Investigations

  • Diagnosis require 2 of:
    • Raised serum testosterone (free testosterone) OR clinical features of hyperadrongenism
    • ‘Polycystic’ ovaries with at least 12 follicles on USS
    • Anovulation/oligo-ovulation (presenting as amenorrhoea/oligoenorrhoea)
  • Hormone profile:
    • LH may be high
    • LH:FSH ratio may be raised (>2)
    • Free testosterone
    • Total testosterone
    • Sex hormone binding globulin (SHBG) is normal or low
  • USS typically shows ovaries of 3x normal volume, with at least 12 follicles >10cm3 volume
    • NB be wary of moderate follicle numbers in adolescence as more follicles are normal
  • TFTs
  • 24-h urinary cortisol
  • Prolactin
  • Fasting glucose

 

Management

  • No medical treatment for both symptoms control and fertility
  • Fertility:
    • Weight loss dramatically improves chances
      • Orlistat
      • Metformin (improves fertility in it’s own right in addition to weight loss properties)
    • Clomifene to induce ovulation
    • Ovarian drilling to stimulate ovulation
  • Symptom control:
    • COC for acne, irregular bleeding
      • At least 3-4 menses per year are recommended to reduce risk of endometrial cancer
      • Progestogens can be used to induce bleeds if the patient isn’t suitable for COC
    • Metformin for control of hyperinsulinaemia, improves insulin sensitivity and helps control weight
    • Co-cyprindrol for hirsuitism and acne, also can be used to induce bleeds
    • Orlistat for control of weight
    • Cosmetic procedures such as electrolysis for hirsuitism
  • Risk reduction:
    • Monitor for diabetes, hypertension, hyperlipidaemia, cholesterolaemia and heart disease as patients are at increased risk
    • Monitor during pregnancy for gestational diabetes, preterm labour and pre-eclampsia. Requires consultant-led care.

 

Prognosis

  • Increased levels of infertility – 70-80% prevalence
  • Increased levels of diabetes (10% have diabetes type 2, 40% have insulin resistance that is independent of obesity, 43% have metabolic disease) and heart disease
  • Increased levels of obesity and associated diseases
  • 3x risk of endometrial cancer as a result of amenorrhoea/oligomenorrhoea
  • 2-3x risk of ovarian cancer
PCOS.docx
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