gestational trophoblastic disease
(jeh-STAY-shuh-nul troh-fuh-BLAS-tik dih-ZEEZ)
Any of a group of tumors that develops from trophoblastic cells (cells that help an embryo attach to the uterus and help form the placenta) after fertilization of an egg by a sperm. The two main types of gestational trophoblastic diseases are hydatidiform mole and choriocarcinoma. Also called gestational trophoblastic tumor.