Postpartum thyroiditis (PPT) is an autoimmune-mediated destructive thyroiditis that occurs in the first year postpartum with a prevalence of 5%. In order to appropriately counsel and treat the patient, physicians need to recognize the signs and symptoms of PPT and distinguish PPT from Graves hyperthyroidism. This review of PPT will discuss the etiology, clinical course, risk factors, prognosis, and treatment of PPT. Understanding PPT is important for all physicians taking care of women in the peripartum period as women who have had PPT are at an increased risk of subsequent episodes of PP and at risk of permanent hypothyroidism.