Uterine fibroids
Uterine fibroids
Uterine fibroids are noncancerous growths of the uterus that often appear during childbearing years. Also called leiomyomas or myomas, uterine fibroids aren’t associated with an increased risk of uterine cancer and almost never develop into cancer.
Fibroids range in size from seedlings, undetectable by the human eye, to bulky masses that can distort and enlarge the uterus. You can have a single fibroid or multiple ones. In extreme cases, multiple fibroids can expand the uterus so much that it reaches the rib cage and can add weight.
In women who have symptoms, the most common signs and symptoms of uterine fibroids include:
- Heavy menstrual bleeding
- Menstrual periods lasting more than a week
- Pelvic pressure or pain
- Frequent urination
- Difficulty emptying the bladder
- Constipation
- Backache or leg pains
- Genetic changes. Many fibroids contain changes in genes that differ from those in typical uterine muscle cells.
Hormones. Estrogen and progesterone, two hormones that stimulate development of the uterine lining during each menstrual cycle in preparation for pregnancy, appear to promote the growth of fibroids.
Fibroids contain more estrogen and progesterone receptors than typical uterine muscle cells do. Fibroids tend to shrink after menopause due to a decrease in hormone production.
- Other growth factors. Substances that help the body maintain tissues, such as insulin-like growth factor, may affect fibroid growth.