Gestational trophoblastic disease is a group of diseases that develop from trophoblast cells. Trophoblast cells help an embryo attach to the uterus and help form the placenta after an egg is fertilised by a sperm.
Sometimes, there is a problem with the egg and the trophoblast cells, and a tumour forms in the uterus instead of a healthy foetus.
Gestational trophoblastic disease is also called gestational trophoblastic tumour.
Gestational trophoblastic disease is different from uterine sarcoma.
About the uterus
Gestational trophoblastic disease starts inside the uterus. The uterus, or womb, is the main female reproductive organ. It is about the size and shape of a hollow, upside-down pear, and sits low in the abdomen between the bladder and rectum. It is joined to the vagina by the cervix, which is the neck of the uterus.
The bulk of the uterus is smooth muscle tissue, which is called the myometrium. The lining of the uterus is called the endometrium.
When women ovulate (produce eggs in their ovaries), an egg travels through the fallopian tube into the uterus. If the egg is fertilised by a sperm, it will implant itself into the endometrium and grow into a foetus.
If the egg is not fertilised, the top layers of the endometrium are shed and flow out of the body through the vagina during menstruation. This is known as your period.
Menopause occurs when a woman no longer releases the hormones that cause ovulation and menstruation. A menopausal woman’s monthly periods stop, and she can no longer become pregnant. The uterus becomes smaller and the endometrium becomes thinner.