Uterine fibroids are common, noncancerous growths that often go entirely unnoticed by patients.

Cultures · Published 10 October 2026 Swipe more like this →

In short: These firm, rubbery masses of smooth muscle tissue are remarkably prevalent during reproductive years, yet many women remain unaware they have them. While often asymptomatic, they can occasionally grow to the size of a grapefruit, causing significant pain, heavy bleeding, or even mimicking the physical appearance of pregnancy.

Uterine fibroids, also known as leiomyomas or myomas, are benign growths that develop within the muscular wall of the uterus. They are not cancerous and do not increase the risk of uterine cancer. While the exact cause remains unclear, they are heavily influenced by the hormones estrogen and progesterone, which promote their growth. This is why fibroids typically appear during a person's reproductive years and often shrink following menopause when hormone levels drop. Research suggests that these growths may originate from a single stem cell in the uterine muscle that divides repeatedly, eventually forming a distinct, fibrous mass.

The clinical presentation of fibroids varies wildly. Many individuals experience no symptoms at all, with the growths only discovered during routine pelvic exams or pregnancy ultrasounds. For others, the impact can be severe. Symptoms are largely dictated by the size, number, and location of the fibroids—whether they are intramural, submucosal, or subserosal. Common issues include heavy or painful menstrual periods, pelvic pressure, frequent urination, and lower back pain. In extreme cases, large fibroids can fill the pelvic or abdominal cavity, causing visible distension. Complications such as anemia can arise from chronic blood loss, sometimes requiring iron supplementation or, in rare instances, blood transfusions.

Treatment is not always necessary, especially if the fibroids are small or asymptomatic. When intervention is required, options range from medications—such as birth control to manage bleeding or GnRH agonists to shrink the growths—to various surgical procedures. Myomectomy allows for the removal of fibroids while preserving the uterus, which is a critical consideration for those planning future pregnancies. Conversely, a hysterectomy is the only definitive cure, as it removes the uterus entirely. Because fibroids can be linked to infertility or pregnancy complications like placental abruption and preterm delivery, patients are encouraged to discuss their specific fertility goals with a healthcare professional when evaluating these medical and surgical pathways.

General information, not professional advice. Spotted an error? Flag the card or see corrections and complaints.

Intellect Plus is a visual educational discovery platform for exploring fascinating facts and ideas. Brain Food, Not Brain Rot. What is Intellect Plus?

Related

• Uterine cancer is two different diseases, with very different outlooks
• Leiomyosarcoma: The Rare and Aggressive Cancer Hiding Within Your Smooth Muscle
• What happens when uterine tissue grows where it shouldn't?
• Endometriosis affects nearly 200 million women, yet diagnosis often takes years
• The uterus is a hormone-tuned cradle for mammalian pregnancy
• The most successful novel that critics absolutely loathed
• A harrowing World War II disaster story met with critical failure on the screen
• The provocative 1980s girl group that Prince envisioned as a modern Supremes
• A billion-dollar warship destroyed by fire, yet the accused sailor walked free
• From Strumica to Wembley: The globetrotting career of manager Veljko Paunović
• How Guns N' Roses turned a Raphael painting into a record-breaking double album
• A psychological thriller leaves audiences questioning who is the true villain of the story

More in UK & Irish culture · More in Cultures · Latest · A–Z · All topics