Masaharu Fukunaga, M.D. Department of Pathology, the Jikei University Daisan Hospital, Tokyo, Japan Hydatidiform moles With the increased use of ultrasound hydatidiform mole (HM) is being diagnosed at increasingly early stages of gestation. As villous edema is not fully developed, we cannot make a diagnosis of HM by macroscopic observation. Furthermore, microscopically the classic features of c...