Signs of Fibroids Breaking Down: Fibroid Degeneration Explained
A large majority of people with uteruses will develop fibroids at some point in their lifetime. What happens when fibroids outgrow their blood supply or begin to break down? Let’s find out.
How are Fibroids Formed?
The cause of fibroids is unknown, although there are a few potential links that researchers have noticed. For example, many people with fibroids have specific genetic mutations and/or a family history of fibroids. [1-2] The hormones estrogen and progesterone also promote the growth of fibroids. When these hormone levels drop, as seen in menopause, fibroids tend to shrink in size. Some researchers also believe that fibroids first develop from a stem cell found in the muscular uterine tissue. [1-2] As this cell divides, it creates a larger growth made up of nearby tissue.  Fibroids can range in size, location, and growth pattern. Some fibroids grow very slowly while others grow rapidly. Read about the different types of fibroids →
Risk Factors for Uterine Fibroids
Fibroids are a common condition in people with female organs of reproductive age, however, there are some additional factors that may increase someone’s risk of developing fibroids [2,3]:
- Race: Black women are more likely to have fibroids and experience severe symptoms.
- Family history: A mother or sister with fibroids increases your risk of having fibroids.
- Early menstruation: Those with an early age of menarche are more likely to develop fibroids.
- Vitamin D deficiency: Lower levels of vitamin D was found to be associated with an increased incidence of fibroids. Shop Vitamin D3 Gummies
- Certain lifestyle factors: Dietary habits such as drinking alcohol, eating high amounts of red meat, and eating fewer vegetables, fruit, and dairy have been shown to increase the risk of fibroids.
What is Fibroid Degeneration?
Fibroid degeneration refers to the decline or breakdown of these uterine growths. This often occurs when a fibroid has outgrown its blood supply. If a fibroid grows to be too large, the connected blood vessels may be unable to provide ample oxygen to maintain the cells.  Cells then begin to die, causing the fibroid to degenerate and shrink in size.  Even after degeneration happens, fibroids can grow again as long as the blood supply and hormones necessary for growth are present. In some cases, treatment for fibroids may be necessary.
What Causes Fibroids to Break Down?
In order for fibroids to continue growing, they need a connection to a uterine artery, attached blood vessels, and the presence of female hormones. [4-5] Fibroids are made up of living cells, meaning they need oxygen and other nutrients to grow. When oxygen or nutrients are unable to get to the fibroid, the cells that make up the fibroid will begin to die. This can happen if a fibroid grows too large for its blood supply, or if there is a blockage of these arteries.  Some researchers also mention that low levels of estrogen and aging may play a role in some cases of degeneration.  Other causes include pregnancy (known as necrobiosis), and torsion, which refers to a fibroid twisting and cutting off its own blood supply. 
Types of Fibroid Degeneration
When fibroids degenerate, the smooth muscle tissue that made up the fibroid can be replaced with other types of cells and tissues. This can make fibroids more difficult to diagnose and differentiate from other growths and conditions. Five types of fibroid degeneration include [6-9]:
- Hyaline: Hyaline degeneration is the most common type of fibroid degeneration. This occurs when the smooth muscle tissue making up the fibroid is replaced by fibrous connective tissue. This is seen in approximately 60% of cases.
- Cystic: Cystic degeneration occurs in about 4% of cases and is more commonly seen after menopause. Cystic fibroids can mimic ovarian cysts and will look similar to a liquid, honeycomb pattern.
- Myxoid: Myxoid degeneration accounts for about 19% of cases. When myxoid degeneration occurs, the fibroid will be filled with a gelatinous substance. The smooth muscle tissue will be replaced with clear, mucus-like connective tissue. Myxoid fibroids generally don’t contain any new cell growth.
- Red: Red degeneration only accounts for about 3% of cases and occurs most often during pregnancy. Red degeneration is a result of a ruptured blood vessel inside the fibroid, causing the fibroid to turn red.
- Calcification: Fibroids can calcify when the cells start dying due to oxygen loss. Calcification occurs in around 8% of cases and transforms the tissue into a hard mass.
What Does Fibroid Degeneration Feel Like?
Degenerative fibroids can cause severe abdominal pain. This may feel one-sided and could last for a few days to a few weeks.  In addition to abdominal or pelvic pain, you may notice other symptoms, especially if the fibroids are fairly large or pressing on other organs or tissues. Common symptoms of fibroids include abnormal vaginal bleeding, abdominal pain, and abdominal pressure.  In some cases, fibroids can cause painful sex, painful urination, and lower back pain. 
Symptoms of Fibroid Degeneration
When a fibroid begins to degenerate, it can cause discomfort or pain. Common symptoms of fibroid degeneration include :
- Acute pain: Sharp, sudden pain in the abdomen, sometimes accompanied by swelling.
- Chronic pain: Longer lasting, less severe pelvic pain.
- Discharge: Some experience fibroid degeneration discharge which may be watery or slightly bloody
Diagnosis and Treatment of Fibroid Degeneration
While treatment isn’t always necessary for fibroids, your healthcare provider may suggest treatment options if fibroids or fibroid degeneration are causing you pain or discomfort. Some options for fibroid pain relief at home include a warm compress, rest, and pain medications.  If you do move forward with fibroid treatment, there are many options including birth control pills, hormone agonists, embolization and ablation, and surgical techniques. [2-4] Speak to your healthcare provider about what options might be right for you.
Fibroids are a common occurrence in women and people assigned female at birth. Fibroids rely on blood supply and hormones in order to continue growing. When the blood supply providing nutrients to fibroids is blocked, or if the fibroid outgrows the blood supply, degeneration can happen. There are a few different types of degeneration, characterized by the cause and type of tissue that grows in place of the smooth muscle tissue. Fibroid degeneration can cause pain, bleeding, fever, and discharge. Treating fibroids can be done through medications, surgery, and other medical interventions. To learn more, visit the Natalist blog.
- Uterine Fibroids. Mayo Clinic. Sept. 21, 2022. URL.
- Florence AM, Fatehi M. Leiomyoma. [Updated 2023 Jan 4]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK538273/
- Uterine Fibroids. Mayo Clinic. September 21 2022. URL. Accessed June 2023.
- Signs of Fibroids Breaking Down. USA Fibroid Centers. URL. Accessed June 2023.
- Shrestha R, Khanal R, Aryal MR, et al. Fibroid degeneration in a postmenopausal woman presenting as an acute abdomen. J Community Hosp Intern Med Perspect. 2015;5(1):25917. Published 2015 Feb 3. doi:10.3402/jchimp.v5.25917
- Brown, D. Uterine Leiomyomas. Systemic Lupus Erythematosus (Fifth Edition), 2011. Science Direct.
- Sharmila V, Babu TA. A Rare Case of Cystic Degenerated Fibroid Masquerading as an Ovarian Mass. Gynecol Minim Invasive Ther. 2022;11(1):71-73. Published 2022 Feb 14. doi:10.4103/GMIT.GMIT_16_21
- Bhuyar S, Sontakke B, Rajbhara PM. Degenerated fibroid - a diagnostic challenge. Int J Reprod Contracept Obstet Gynecol 2017;6:292-4
- J. Karthiga Prabhu, Sunita Samal, Shanmugapriya Chandrasekar, Divya Subramani, and Shanmugapriya Rajamanickam. A Massive Degenerative Leiomyoma Mimicking an Ovarian Tumor: A Diagnostic Dilemma. Journal of Gynecologic Surgery.Feb 2021.67-69.http://doi.org/10.1089/gyn.2020.0118
- Living with uterine fibroids. NIH. Medline Plus. January 10 2022. URL.