Fibroidsare benign tumors that develop in the womb. The terms that are also used forfibroids are uterine myomas, fibromyomas or leiomyomas. Over 30 percent ofwomen have fibroids and some of them don’t even know it. Fibroids are locatedon the uterine wall and they stay there, without any danger that they will moveoutward. The number of fibroids can vary, but most commonly that number is fromfour to seven. Fibroids can be intramural, subserosal, sub mucosal andpedunculated. Fibroids can be very small, but they can also grow up to 20 cmwide. Estrogen is the hormone that increases the chances for fibroid growth. Inwomen who are in their menopause and have low level of estrogen fibroids getsmaller. During the pregnancy, fibroids can even become smaller. However,there are some fibroids such as sub mucosal, which can affect the possibilityof staying pregnant. Fibroids rarely cause miscarriage, premature birth orbleeding. If you have fibroids during pregnancy, consult your doctor. The caseswhere fibroids are transforming into cancer are very rare.