What are uterine fibroids?

Uterine fibroids are the most common tumors of the female reproductive system. Fibroids—also called uterine myomas, leiomyomas or fibromas—are benign growths that develop from smooth muscle cells and fibrous connective tissue either just beneath the outer surface of the uterus, or within the uterine wall. Fibroid growth is linked to the presence of estrogen and progesterone, but the mechanism involved is not understood. Fibroids range from the size of a pea to the size of a grapefruit. As many as 50 percent of women develop uterine fibroids at some point in their lives, but because fibroids may not produce symptoms, many women are unaware that they have them.

Dr. Jessica A. Shepherd, MD
OBGYN (Obstetrician & Gynecologist)

Uterine fibroids are the most common benign tumors in women; the incidence is high, but not every woman experiences symptoms. Watch OBGYN specialist Jessica Shepherd, MD, explain what uterine fibroids are, as well as some of the main symptoms.

Donna Hill Howes, RN
Family Practitioner

Fibroids are muscular tumors that grow in the wall of the uterus (womb). Another medical term for fibroids is "leiomyoma" (leye-oh-meye-OH-muh) or just "myoma." Fibroids are almost always benign (not cancerous). Fibroids can grow as a single tumor, or there can be many of them in the uterus. They can be as small as an apple seed or as big as a grapefruit. In unusual cases they can become very large.

This information is based on source information from the National Women's Health Information Center.

Debra Fulghum Bruce PhD
Healthcare Specialist

Uterine fibroids (myomasor leiomyomas) are the most common tumors in the female reproductive system. It is estimated that four out of five women over the age of thirty-five have uterine fibroids.

Dr. Ashley B. Briggs, MD
OBGYN (Obstetrician & Gynecologist)

Uterine fibroids can cause problems—but much of the time, women don't even know they're there. In this video, Dr. Ashley Briggs explains the signs that should make you talk to your doctor.

Fibroids are the most common benign pelvic tumor in women. They arise from the muscular layer of the uterus called the myometrium. They occur in reproductive-aged women and can lead to pelvic pain and pressure as well as uterine bleeding. They may also affect fertility and pregnancy.

Dr. Kevin W. Windom, MD
OBGYN (Obstetrician & Gynecologist)

Uterine fibroids are benign tumors of the uterus, also known as leiomyomata. Fibroids can cause severe problems with pelvic pressure, pelvic pain, heavy menstrual cycles, abdominal distention and abdominal bloating. Fibroids are the number one reason that women in the United States undergo hysterectomies. Fibroids are seen much more commonly in African American patients for unknown reasons.

Dr. Mehmet Oz, MD
Cardiologist (Heart Specialist)

Fibroids are noncancerous growths of cells that start in the muscular layer of the uterine wall. There are different types. Watch the animation to learn more about uterine fibroids.

Dr. Evelyn Minaya, MD
OBGYN (Obstetrician & Gynecologist)

Watch as obstetrician and gynecologist Dr. Evelyn Minaya gives the definition of uterine fibroids.

Uterine fibroids, or myomas, are non-cancerous tumors that develop in the wall of the uterus. These growths are made up of muscle and fibrous tissue, and they can form in many different parts of the uterus. Uterine fibroids are actually quite common, and they often don't cause any noticeable symptoms. If they do cause problematic symptoms, they may be treated with medications or surgery.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.