Background: Little is known about Sheehan's syndrome (SS), even though it is believed that its incidence is low. The aims of this study were to determine the clinical features and diagnostic delay of SS and to ascertain whether early signs could have allowed earlier diagnosis. Subjects and methods: All patients with SS diagnosed in reference units in the southeast of France between 1980 and 2011 were recruited for this study. Data on obstetrical history, clinical symptoms suggestive of hypopituitarism, early signs, hormone analysis, and magnetic resonance imaging were collected. Results: Of the 40 women found to have SS, 39 were studied. Mean delay in the diagnosis of SS was 9G9.7 years. We found that four of the 35 assessable patients were diagnosed with agalactia, 16 of the 29 assessable ones with amenorrhea, 19 of the 39 with hypothyroidism, eight with acute adrenal insufficiency, and 15 with asthenia. Among the patients for whom there was a diagnostic delay of more than 1 year (nZ28), seven had headaches during the postpartum period, all assessable patients had agalactia, six of the 22 assessable ones had amenorrhea, seven of 28 had hypothyroidism, and 12 of 28 had asthenia. Conclusion: Most signs of SS are aspecific and classical signs such as agalactia and amenorrhea are often difficult to detect, which can explain the long diagnostic delay. We suggest that all women failing to lactate after postpartum hemorrhage (PPH) should be evaluated by measuring prolactin levels and women with signs such as amenorrhea and asthenia, even several years after PPH, should undergo a blood test including assessment of thyroxine, TSH, 0800 h ACTH-cortisol, and IGF1 levels.