🔑 Key Learning

  • Caused by pituitary infarction secondary to severe postpartum haemorrhage.
  • Leads to hypopituitarism, with symptoms such as lactation failure, amenorrhoea, and fatigue.
  • Diagnosis is clinical with hormonal assays confirming pituitary hormone deficiencies.
  • Managed with lifelong hormone replacement therapy.

🧬 Pathophysiology

  • Severe postpartum haemorrhage or hypotension causes ischaemia and infarction of the anterior pituitary.
  • The enlarged pituitary gland during pregnancy is more susceptible to ischaemia.
  • Results in reduced or absent production of one or more anterior pituitary hormones → hypopituitarism.

👀 Clinical Features

  • Symptoms may appear days to months postpartum.
  • Common features include:
    • Failure to lactate
    • Amenorrhoea or oligomenorrhoea
    • Fatigue and weakness
    • Cold intolerance (due to secondary hypothyroidism)
    • Weight loss, hypotension, dizziness (due to adrenal insufficiency)
    • Loss of pubic/axillary hair
  • Severe cases may present with panhypopituitarism and adrenal crisis.

🧪 Investigations

  • Clinical history of severe postpartum haemorrhage or hypotension.
  • Hormonal profile:
    • Low cortisol, TSH, free T4, LH, FSH, oestradiol, and prolactin
  • MRI pituitary may show an empty sella or pituitary atrophy.

💊 Management

  • Lifelong hormone replacement tailored to deficiencies:
    • Hydrocortisone or prednisolone for adrenal insufficiency
    • Levothyroxine for secondary hypothyroidism
    • Oestrogen and progesterone if premenopausal
    • Growth hormone replacement in selected cases
  • Educate patients on adrenal crisis and the need for steroid cover during illness or surgery.
  • Regular endocrine follow-up to adjust therapy.

📝 Exam Clues & Clinchers

  • Woman with history of PPH, failure to lactate, fatigue, amenorrhoea → suspect Sheehan syndrome.
  • Secondary hypothyroidism and adrenal insufficiency suggest pituitary cause.