This report reviews proliferative diseases of intermediate trophoblast cells and summarises clinical findings and pathohistological and immunohistochemical features of a placental site nodule. This recently described entity is an endometrial or endocervical benign proliferation of intermediate trophoblast cells occurring after intrauterine gestation. Patients usually present with a history of abnormal vaginal bleeding and frequently cells that are present in their cervical smears are misinterpreted as squamous dysplasia. In such cases it is important to distinguish the placental site nodule from squamous lesions or decidual polyps; this is possible by means of immunohistochemistry.