Uterine fibroids, also known as leiomyomas or myomas, are common non-cancerous growths that develop in or around the uterus. Composed of muscle and fibrous tissue, they vary significantly in size. Many individuals experience no symptoms. Intramural fibroids are particularly common, characterized by their specific location within the muscular wall of the uterus.
Understanding Intramural Fibroids
Intramural fibroids are the most common type of uterine fibroid, characterized by their growth directly within the myometrium, the thick, muscular wall of the uterus. Unlike subserosal fibroids (on the uterus’s outer surface) or submucosal fibroids (beneath the inner uterine lining), intramural fibroids are embedded within the muscle fibers. This distinction is important, as their location significantly influences symptoms and potential treatments.
These fibroids can vary considerably in size, from microscopic to over 20 centimeters (8 inches) in diameter, sometimes causing the uterus to appear pregnant. They can occur as a single growth or in clusters. Their specific position within the uterine wall also matters; they can be anterior (front), posterior (back), or fundal (top), with each location potentially affecting adjacent organs or uterine function differently. For instance, a large intramural fibroid in the fundal area could impact fertility or pregnancy progression. While the precise cause of uterine fibroids is not fully understood, research indicates that hormones like estrogen and progesterone are involved in their growth, and genetic predispositions may also play a role.
Recognizing Symptoms and Diagnosis
When symptoms do occur, their type and severity often depend on the fibroids’ size, number, and exact location within the uterine wall. One common symptom is heavy menstrual bleeding, also known as menorrhagia, which can lead to anemia and fatigue due to significant blood loss. Bleeding between periods or prolonged menstrual cycles lasting over 10 days can also occur.
Pelvic pain and pressure are frequently reported, manifesting as a feeling of fullness or heaviness in the lower abdomen. This discomfort can extend to the lower back, and some individuals experience pain during sexual intercourse. Depending on their size and location, intramural fibroids can also press on nearby organs like the bladder or bowel, leading to frequent urination, difficulty emptying the bladder, or constipation.
Diagnosis often begins with a routine pelvic exam, where a healthcare provider might feel an enlarged or irregularly shaped uterus. Imaging tests then confirm and characterize the fibroids. Ultrasound, particularly transvaginal ultrasound, is a common initial method, providing detailed images. Magnetic Resonance Imaging (MRI) offers more comprehensive detail regarding fibroid size, number, and precise location, valuable for treatment planning. In some cases, a hysteroscopy, inserting a thin scope into the uterus, might visualize the uterine cavity, especially to investigate abnormal bleeding or suspected submucosal components.
Managing Intramural Fibroids
The approach to managing intramural fibroids varies widely, depending on the severity of symptoms, the fibroids’ size and location, and the individual’s desire for future fertility. For those with no symptoms or only mild ones, watchful waiting is a common strategy. This involves periodic monitoring to track any changes in fibroid size or symptom progression, as fibroids often grow slowly or even shrink after menopause.
When symptoms necessitate intervention, medical therapies are often the first line of treatment. Non-steroidal anti-inflammatory drugs (NSAIDs) can help manage pain and reduce heavy bleeding. Hormonal medications, such as birth control pills, progestin-releasing intrauterine devices (IUDs), or gonadotropin-releasing hormone (GnRH) agonists, can significantly reduce heavy menstrual bleeding and sometimes shrink fibroids by modulating hormone levels. GnRH agonists are typically used temporarily, often to shrink fibroids before surgery, as their effects are temporary and can have menopausal side effects.
For more persistent or severe symptoms, interventional procedures or surgery may be considered. Uterine fibroid embolization (UFE) is a minimally invasive procedure where small particles are injected into the arteries supplying the fibroids, cutting off their blood supply and causing them to shrink. Myomectomy is a surgical option that removes only the fibroids while preserving the uterus, making it suitable for individuals who wish to retain fertility. Hysterectomy, the surgical removal of the entire uterus, is considered a permanent solution for fibroids, particularly when other treatments have not been effective or for very large fibroids.