[The early placental trophoblast. II. Tumorous disorders of trophoblast development].

Many factors can alterate the correct implantation of the blastocyste, e.g. alterations of the tubal micro-environment or inflammatory processes. For correct implantation a mature endometrium is necessary. Other alterations, which can cause an abortion are immunological mechanisms. Gestational trophoblastic disease includes the partial and complete hydatidiform mole, as well as the chorioncarcinoma. Proliferations of the intermediate trophoblast are the placental site nodule or plaque, the exaggerated placental site and the placental site trophoblastic tumor. The distinction of the different causes of malimplantation and abortion are necessary to prevent a further disruption of a following pregnancy.