Ovarian mature teratoma with homunculus coexisting with an intrauterine pregnancy

The pathologic and radiographic findings of a homunculus originating in a mature ovarian teratoma are described and compared with those of 22 cases reported in the literature. To our knowledge, this is the first instance of an ovarian homunculus occurring simultaneously with an intrauterine pregnancy. In this case the upper extremities were better developed than the lower extremities. This was in contrast to the better developed lower extremities reported previously.