Uterine fibroids are common growths of the uterus that often appear during the years of reproductive age. They are not cancerous and rarely become cancerous. Uterine fibroids are also known as leiomyomas or myomas. Fibroids vary in number and size, and some may be too small to be seen with the naked eye. Others can grow to the size of a grapefruit or larger, potentially distorting the uterus and causing symptoms.

Many people have uterine fibroids at some point in their lives, but they may not be aware of them due to a lack of symptoms. Fibroids can be found during a pelvic exam or pregnancy ultrasound. While the exact cause of uterine fibroids is unclear, factors such as gene changes, hormones, growth factors, and extracellular matrix may play a role.

Symptoms of uterine fibroids can vary depending on the location, size, and number of fibroids. Common symptoms include heavy menstrual bleeding, painful periods, pelvic pressure, frequent urination, and constipation. In rare cases, a fibroid can cause sudden, severe pain when it outgrows its blood supply and begins to die.

Fibroids are often grouped by their location, including intramural, submucosal, and subserosal fibroids. It is essential to see a doctor if symptoms persist or worsen over time. Risk factors for uterine fibroids include reproductive age, Black race, family history, early menstruation, obesity, low vitamin D levels, diet, and alcohol consumption.

Complications of uterine fibroids can arise, including anemia, infertility, pregnancy loss, and pregnancy complications such as placental abruption and preterm delivery. Researchers continue to study the causes of fibroid tumors, and more research is needed on prevention. However, healthy lifestyle changes and certain contraceptives may lower the risk of fibroids. Mayo Clinic experts provide comprehensive care for uterine fibroids, including diagnosis, treatment, and management.