Uterine Fibroid / Fibroids
Uterine fibroids—also called leiomyomas—are common benign growths that develop in the muscle wall of the uterus. They can range in size from tiny nodules to large masses that distort the shape of the uterus. Many fibroids cause no symptoms and are found incidentally on imaging, while others may lead to heavy periods, pelvic pain, or pressure symptoms. Fibroids are noncancerous and do not increase the risk of uterine cancer.
What is it?
Fibroids form when muscle cells in the uterine wall grow in a circular pattern, creating firm, rubbery nodules. They may grow within the uterine wall, project outward, or protrude into the uterine cavity. Hormones—especially estrogen and progesterone—play a major role in their growth, which is why fibroids may enlarge during reproductive years and shrink after menopause.
Ultrasound is usually the first imaging test to detect fibroids and identify their size, number, and location. MRI provides detailed mapping when planning treatment or when fibroids are numerous or large. CT may show fibroids incidentally but is not the primary diagnostic tool.
Important to Know
Fibroids are benign tumors and typically grow slowly. Not all fibroids require treatment; decisions depend on symptoms, size, and impact on fertility or quality of life. Some treatments shrink fibroids, while others remove them completely. Pregnancy is still possible for many individuals with fibroids, depending on their size and location.
Red flag symptoms include very heavy bleeding that causes dizziness or anemia, sudden severe pelvic pain (possible degeneration or torsion of a pedunculated fibroid), persistent bladder or bowel symptoms, or rapid abdominal enlargement. These warrant timely medical evaluation.