“Fibroid” is a common lay term used to describe a benign neoplasm (new growth) that arises from smooth muscle cells. The medical name of these benign tumors is “leiomyoma”. Fibroid is a misnomer in that the tumor consists of smooth muscle cells rather than fibrous tissue.
Although leiomyomas can arise in smooth muscle anywhere throughout the body, the term “fibroid” refers to these lesions when they occur in the uterus (womb).
The uterus is made up of mostly smooth muscle. It has an outer serosa, and an internal cavity lined by endometrium. At the beginning of pregnancy the fertilized ovum implants in the uterine endometrial lining. In a non-pregnant woman of reproductive age the endometrium sheds cyclically each month as menstruation.
Uterine leiomyomas (fibroids) are the most common benign tumor in women. They occur most often during the reproductive years, usually sometime after age 20, and are more common in African American women than in Caucasians. Approximately one in five women will develop fibroid(s) during their reproductive years. Fibroids are often multiple, and their size can range from microscopic to massive.
Within the uterus, fibroids can be in the uterine wall itself (intramural fibroid), bulging beneath the outer uterine serosa (pedunculated subserosal fibroid), or immediately beneath the endometrial lining (submucosal fibroid).
Submucosal fibroids cause abnormal uterine bleeding between periods.
Intramural fibroids, if large, can cause a feeling of pelvic pressure, and cramping periods.
Subserosal fibroids rarely cause symptoms unless very large.
Diagnosis of fibroids is by pelvic examination, with confirmation by pelvic ultrasound.
Fibroids do not become malignant and need not be removed unless they are symptomatic or interfere with fertility. The treatment is surgical removal. Fibroids depend on estrogen for growth, and symptoms due to fibroids often improve with the use of birth control pills.
Fibroid is the common term used for uterines fibroids. Uterines fibroids is leimyoma originating in the uterus. Fibroids are the most common benign tumors in females and is typically found during the middle and later reproductive years. They can grow and cause heavy and painful menstruation.
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