A fibroid is the most common tumor (abnormal mass of tissue) found in the pelvis. Such a tumor develops most often between the ages of 35 and 45 years, seldom before age 20. Fibroids do not occur at all before puberty. After a woman completes menopause, they generally stop growing and may even disappear.
Usually a fibroid is found in the uterus where it is the most common form of uterine mass. A fibroid can also develop on another structure that contains smooth muscle cells. In vary rare cases, it can even “invade” another organ when it grows too large to confine itself to its original location.
Parasitic fibroid. When a fibroid attaches itself to another organ, it transforms itself into the rarest of all types, the parasitic fibroid. As the tumor establishes a new source of blood, its uterine stalk gradually degenerates until the fibroid is no longer attached to the uterus at all.



