Uterine fibroids: definition and meaning
Uterine fibroids are noncancerous growths made of muscle and fibrous tissue that develop in or on the uterus. They're very common: by age 50, most women and people with a uterus have at least one, and Black women are affected earlier and more often. Many cause no symptoms, but some lead to heavy periods, pelvic pressure or pain.
Types of fibroids
| Type | Where it grows | Often causes |
|---|---|---|
| Submucosal | Just under the lining, into the uterine cavity | Heavy bleeding, fertility problems |
| Intramural | In the muscle wall | Heavy periods, pressure |
| Subserosal | On the outside of the uterus | Pressure on bladder or bowel |
| Pedunculated | On a stalk | Pain if it twists |
How they relate to your cycle
Fibroids are fed by estrogen and progesterone, so they can grow during the reproductive years and usually shrink after menopause. They can make periods longer and heavier, with clots, and cause bleeding between periods.
Why it matters
Heavy bleeding from fibroids is a leading cause of iron deficiency anemia, which brings tiredness, breathlessness and low mood. Pelvic pressure, frequent peeing and back pain can wear you down too. Treatments range from watchful waiting to medicines, a hormonal IUD, procedures that shrink fibroids, and surgery. Compare with adenomyosis and see heavy menstrual bleeding.
See a doctor if you have heavy periods, pass large clots, feel tired or breathless, notice a swollen belly, pelvic pressure or frequent peeing, or have trouble getting pregnant. Get urgent care for sudden severe pelvic pain.
Frequently asked questions
Can fibroids turn into cancer?
Very rarely. Fibroids are benign, and cancerous growths in the uterine muscle are uncommon and thought to be separate from fibroids.
Do fibroids go away on their own?
They often shrink after menopause. Before then, small fibroids that cause no symptoms are usually just monitored.
Sources
This page is for information only and isn鈥檛 medical advice. If something worries you, please talk to a doctor.
Keep reading
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Adenomyosis: definition and meaningAdenomyosis means the uterine lining grows into the muscle wall of the uterus. A plain-English definition, common symptoms and when to see a doctor.
Heavy periods: what counts as heavy and what helpsHow to tell if you have heavy periods: soaking a pad every hour or two, clots, bleeding over 7 days. Causes, treatments that work, and when to get help.
Iron deficiency anemia: definition and meaningIron deficiency anemia is when low iron means your blood can't carry enough oxygen. Why heavy periods cause it, the symptoms, and what to ask your doctor.Why is my period so heavy? Common causes and what helpsWhy is my period so heavy? Fibroids, polyps, adenomyosis, hormone changes, an IUD or a bleeding disorder are common causes. What helps and when to get help.