This entity, due to the pituitary lymphoplasmacytic infiltrate, was described for the first time in 1962. The clinical suspicion relies on a rapidly progressing hypopituitarism, particularly with adrenal involvement, affecting women in the peripartum period or patients with previously recognized autoimmune disease. Diabetes insipidus is also often reported. A sellar mass is found in 80% of cases. The diagnosis is confirmed by histology, due to the absence of a specific serological test. The endocrine deficiencies are frequently definitive. Corticotherapy is usually effective in reducing neurological symptoms due to pituitary enlargement, and frequently allows to avoid surgery. The disease-related deaths were due to acute adrenal insufficiency or ineffectively treated hypopituitarism. We are reporting a clinical case of probable lymphocytic hypophysitis in the early post partum of a woman with depression and Graves disease. She has hyperprolactinemia and ACTH deficiency, without pituitary changes in the magnetic resonance imaging. She was treated and her depression and hyperthyroidism were relieved. Hyperprolactinemia recovered spontaneously but she still needs glucocorticoid substitution.