A uterine fibroid is a leiomyoma (benign (non-cancerous)
tumor from smooth muscle tissue) that originates from the smooth muscle layer
(myometrium) of the uterus. Fibroids are often multiple and if the uterus
contains too many leiomyomata to count, it is referred to as diffuse uterine
leiomyomatosis. The malignant version of a fibroid is extremely uncommon and
termed a leiomyosarcoma.
Other common names are uterine leiomyoma,[1] myoma,
fibromyoma, fibroleiomyoma.
Fibroids are the most common benign tumors in females and
typically found during the middle and later reproductive years. While most
fibroids are asymptomatic, they can grow and cause heavy and painful
menstruation, painful sexual intercourse, and urinary frequency and urgency.
Some fibroids may interfere with pregnancy although this appears to be very
rare.[2]