Postpartum necrosis of the anterior pituitary gland is known as Sheehan's syndrome in honor of Harold Leeming Sheehan who characterized the syndrome as the consequence of ischemia after severe puerperal hemorrhage. With advancements of obstetrical care, Sheehan's syndrome has become uncommon except in developing countries. In many affected women, anterior pituitary dysfunction is not diagnosed for many years after the inciting delivery. This review emphasizes the long period of time that may elapse between the puerperal hemorrhage and the eventual diagnosis of hypopituitarism. The pathophysiology, epidemiology, clinical features and treatment of this disorder are discussed.