Sheehan's Syndrome

The normal pituitary gland increases in volume during pregnancy, primarily as a result of estrogen-induced lactotroph hyperplasia. For this reason, the pituitary gland is susceptible to ischemic damage and necrosis in patients who experience severe postpartum hemorrhage. This entity, Sheehan's syndrome, is a rare occurrence in developed countries today, but still occurs occasionally. It is probably much more common in developing countries, where it could be a major cause of hypopituitarism. Patients can present with acute hypopituitarism in the postpartum period, or the diagnosis can be made decades after the event in patients who have had chronic, nonspecific symptoms. Classically, the presenting symptom is failure to lactate, but patients can present with a spectrum of clinical findings that reflect variable loss of anterior pituitary gland function. Overt diabetes insipidus is unusual in Sheehan's syndrome, although subtle defects in posterior pituitary function are common. The treatment of Sheehan's syndrome includes standard replacement therapy for hormone deficiencies. The long-term prognosis for patients who develop Sheehan's syndrome is permanent hypopituitarism, requiring lifelong therapy, although there are rare case reports of recovery of pituitary function.