Uterine fibroids are common, non-cancerous growths that develop within or on the uterus. They are a frequent gynecological finding in women during their reproductive years. While not all fibroids cause symptoms, they can significantly impact a person’s health and quality of life.
Understanding Uterine Fibroids
Uterine fibroids, also known as leiomyomas or myomas, are composed of smooth muscle cells and fibrous connective tissue. They can vary in size, from microscopic to larger than a grapefruit, sometimes even reaching the size of a melon, appearing as a single growth or in clusters. Estimates suggest that between 70% and 80% of women will develop fibroids by age 50.
Fibroids are classified by their location within the uterus. Intramural fibroids grow within the muscular wall and are the most common type. Subserosal fibroids develop on the outer surface, sometimes growing into the pelvis. Submucosal fibroids grow just beneath the inner lining and protrude into the uterine cavity, often causing the most severe symptoms. Pedunculated fibroids, a less common type, attach to the uterus by a stalk and can be either submucosal or subserosal.
How Fibroids Cause Heavy Bleeding and Clots
Fibroids can lead to heavy menstrual bleeding, known as menorrhagia, and the formation of blood clots through several mechanisms. Large or multiple fibroids can increase the surface area of the uterine lining, resulting in a heavier flow. Submucosal fibroids are strongly associated with heavy bleeding due to their position within the uterine cavity.
Fibroids can also interfere with the uterus’s natural ability to contract effectively during menstruation. Uterine contractions are important for helping to shed the lining and constrict blood vessels; fibroids can disrupt this, leading to prolonged and excessive bleeding. Fibroids can stimulate the growth of new blood vessels within the uterine wall, contributing to increased blood loss. Large fibroids may also compress surrounding blood vessels, potentially slowing blood flow and increasing the likelihood of clot formation.
When Fibroid Tissue Passes
While fibroids themselves are generally firmly attached to the uterine wall and do not typically pass out as intact “clots,” specific circumstances can lead to the expulsion of fibroid-related tissue. This occurs when a fibroid undergoes degeneration or necrosis, outgrowing its blood supply and breaking down. The dead or dying tissue may then be expelled through the cervix and vagina.
This expelled material is usually necrotic tissue or a detached portion of a fibroid. It can appear as large, irregular clots or fleshy tissue fragments. Pedunculated submucosal fibroids, attached by a stalk, are most likely to be expelled if their blood supply is compromised or the stalk twists. The expulsion process can cause significant cramping, similar to labor pains, as the uterus contracts to push out the material.
When to Seek Medical Attention
Seek medical attention if you experience certain symptoms related to fibroids or heavy bleeding. Severe or prolonged bleeding, such as soaking through sanitary products hourly for several consecutive hours, warrants immediate evaluation. Passing very large blood clots, especially those larger than a quarter, or expelling unusual tissue, are also reasons to consult a healthcare provider.
Symptoms of anemia, including extreme fatigue, shortness of breath, dizziness, or pale skin, can indicate significant blood loss and should be addressed promptly. Severe or sudden pelvic pain and cramping unrelieved by over-the-counter medication also warrant a medical visit. Any new or worsening fibroid symptoms, fever, or foul-smelling vaginal discharge could signal complications like infection.