From the Guidelines
Uterine fibroids cause bleeding primarily by disrupting the normal structure and function of the uterus, leading to heavier menstrual bleeding, and this is supported by the most recent evidence from 2024 1. The exact mechanism of bleeding in uterine fibroids involves several factors, including:
- Distortion of the uterine cavity and increase in the surface area of the endometrium, leading to heavier menstrual bleeding
- Interference with the normal contraction of uterine muscles that help control bleeding during menstruation
- Compression of blood vessels in the uterine wall, causing them to become enlarged and more fragile, which can result in increased bleeding
- Disruption of the normal hormonal environment of the uterus, leading to irregular bleeding between periods Submucosal fibroids, which grow into the uterine cavity, typically cause the most significant bleeding problems because they directly impact the endometrium, as noted in the 2024 study 1. The size, location, and number of fibroids all influence the severity of bleeding symptoms, and treatment options include medications like tranexamic acid or hormonal therapies to reduce bleeding, or procedures such as myomectomy, uterine artery embolization, or hysterectomy for more severe cases, depending on the patient's symptoms and fertility desires, as discussed in the 2024 study 1. Some key points to consider in the management of uterine fibroids and bleeding include:
- First-line medical management includes estrogen-progestin oral contraceptive pills and progestin-containing IUDs, which reduce bleeding symptoms 1
- Second-line medical management includes parenteral GnRH agonists and oral GnRH antagonists, which can reduce bleeding symptoms and tumor volume, but may have hypoestrogenic effects 1
- Progesterone receptor modulators, such as ulipristal acetate, may also be effective in reducing bleeding and bulk symptoms, but their use is limited by reports of hepatotoxicity 1 The most effective treatment approach will depend on the individual patient's symptoms, fertility desires, and overall health status, and should be guided by the most recent and highest-quality evidence, such as the 2024 study 1.
From the Research
Uterine Fibroids and Bleeding
- Uterine fibroids are a common cause of abnormal uterine bleeding, with approximately 30% of cases affecting the quality of life and women's health 2, 3, 4, 5, 6.
- The exact mechanism of how uterine fibroids cause bleeding is not fully understood, but several theories have been proposed, including:
- Aberrations in vascular architecture and network, leading to irregular blood flow and heavy menstrual bleeding 5.
- Formation of a pseudocapsule around intramural fibroids, which may contribute to the disruption of normal blood flow 5.
- Blocking of normal blood flow by uterine fibroids, leading to the formation of venous trunks or venous lakes 5.
- Increased local action of vasoactive growth factors, which may contribute to the development of heavy menstrual bleeding 5.
Symptoms and Treatment
- Symptoms of uterine fibroids include heavy menstrual bleeding, pelvic pain, infertility, and other reproductive issues 2, 3, 4, 5, 6.
- Treatment options for uterine fibroids include medical therapies, such as hormonal contraceptives, tranexamic acid, and nonsteroidal anti-inflammatory drugs, as well as surgical and radiologically guided interventions 2, 3, 4, 6.
- The choice of treatment depends on the size and location of the fibroids, the patient's age, symptoms, and desire to maintain fertility, as well as the experience of the physician 2, 3, 4.