top of page

What are Uterine Fibroids?

Rina Carlini, PhD

Reviewed by Rina Carlini, PhD, Henry Xu, PhD and Joanne Tejeda, PhD

July 12, 2024

What are Uterine Fibroids?

Uterine fibroids, also known as leiomyomas or myomas, are non-cancerous growths in the uterus composed of muscle and fibrous tissue. They can range in size from a pea to as large as a melon. 


Globally, there are 226 million cases of uterine fibroids, with the highest prevalence among women aged 40-50. About 80% of women will develop uterine fibroids in their lifetime.


 In the United States, about 26 million women aged 15 to 50 that are diagnosed with fibroids [1]. By age 50, nearly 80% of Black women and 70% of white women will develop fibroids.  While experiences vary, about 25% of women with fibroids suffer from severe symptoms requiring treatment [2].  



What Causes Uterine Fibroids?  

The exact cause of uterine fibroids is not fully understood, but several factors are believed to contribute to their development, these include [3]: 


  1. Hormones that regulate the menstrual cycle, estrogen and progesterone, promote the growth of fibroids. When hormone levels drop after menopause, fibroid growth tends to decrease [4]. 

  2. Evidence suggests that family genetics is a contributing factor as uterine fibroids tend to occur within the family [5]. 

  3. Race is a key factor for uterine fibroids, as African-American women are 3-times more likely to develop fibroids and at a younger age compared to women of other racial groups [6]. 

  4. Obesity has been linked to an increase in the risk of fibroids [7]. 

  5. Vitamin D deficiency is also associated with increased risk of uterine fibroids [8]. 

  6. Women with high blood pressure typically have a significantly higher risk of developing uterine fibroids [5]. 



Symptoms of Uterine Fibroids [2]: 


  • Heavy menstrual bleeding 

  • Prolonged periods (lasting more than a week) 

  • Iron Deficiency Anemia 

  • Pelvic pain or pressure 

  • Frequent urination 

  • Difficulty emptying the bladder 

  • Constipation 

  • Backache  

  • Leg pains 

  • Reproductive issues, such as infertility or pregnancy complications 


 
Diagnosis of Uterine Fibroids: 

Diagnosis typically begins with taking the patient’s history and identifying symptoms related to uterine fibroids. A pelvic exam is then conducted to check for irregularities in the shape and size of the uterus. In certain cases, blood tests may be conducted to rule out other causes of symptoms, like anemia from heavy bleeding. 


Imaging tests are crucial for an accurate diagnosis. Ultrasound is the primary imaging technique used due to its ability to visualize fibroids and assess their size, number, and location. Saline infusion, involving the injection of a salt solution into the uterus, is often used to create clearer ultrasound images [9].   


Magnetic resonance imaging (MRI) is another valuable tool, especially for detailed mapping of fibroids, which is essential for treatment planning. MRI also helps distinguish fibroids from other pelvic conditions. Other traditional imaging techniques include hysteroscopy, which allows direct visualization of the uterine cavity using a thin, lighted scope, aiding in the identification of fibroids. [10]. 



Treatments of Uterine Fibroids: 

​Medications ​


For mild symptoms, over-the-counter pain relief can be used. Hormonal treatments, such as oral contraceptives or special injections that lower hormone levels, can also help shrink fibroids [4]. 


Non-Invasive Procedures ​


Radiofrequency ablation is a procedure that uses radio energy and heat to remove uterine fibroids. It is performed with a small, energized probe that is passed through the vagina and cervix into the uterus, guided by ultrasound throughout the procedure [11]. 


Minimally Invasive Procedures ​


Uterine artery embolization (UAE) is a treatment in which surgeons inject small particles into the arteries surrounding the fibroid to cut off its blood flow, causing it to shrink [12].  Radiofrequency ablation can also be used in minimally invasive procedures, where laparoscopic scopes are inserted into small incisions to guide the procedure [13].  


Traditional Surgical Procedures ​


An abdominal myomectomy involves making an incision in the abdominal wall to access the uterus and surgically remove fibroids from its surface.  For women with severe symptoms who do not plan on having more children in the future, hysterectomy is used as a last resort [14]. 


​Treatment of uterine fibroids can be time-consuming. Many women often go through multiple doctor visits before being diagnosed, and up to 32% of diagnosed women wait more than 5 years before seeking treatment [2]. Improved access to educational resources is needed to help guide women in their journey when seeking treatment for uterine fibroids. 


New Medical Innovations ​


Medical device innovators are constantly developing new treatment tools for the non-invasive removal of uterine fibroids. Radiologist Dr. Elizabeth David at Sunnybrook Health Sciences Centre in Toronto is working on shrinking fibroids using high-intensity focused ultrasound guided by MRI. She recently completed a clinical trial in which 90% of patients reported being symptom-free after the procedure. [15].

References: 

[1] Lou, Zheng et al. “Global, regional, and national time trends in incidence, prevalence, years lived with disability for uterine fibroids, 1990-2019: an age-period-cohort analysis for the global burden of disease 2019 study.” BMC public health vol. 23,1 916. 19 May. 2023, doi:10.1186/s12889-023-15765-x


[2] Society for Women's Health Research. Uterine Fibroids Toolkit: A Patient Empowerment Guide. Society for Women's Health Research, 2023. 


[3] Stewart, E A. “Uterine fibroids.” Lancet (London, England) vol. 357,9252 (2001): 293-8. doi:10.1016/S0140-6736(00)03622-9 


[4] Bulun, Serdar E. “Uterine fibroids.” The New England journal of medicine vol. 369,14 (2013): 1344-55. doi:10.1056/NEJMra1209993 


[4] American College of Obstetricians and Gynecologists. “Management of Symptomatic Uterine Leiomyomas.” ACOG Practice Bulletin No. 228, July 2021. 


[5] Stewart, E A et al. “Epidemiology of uterine fibroids: a systematic review.” BJOG : an international journal of obstetrics and gynaecology vol. 124,10 (2017): 1501-1512. doi:10.1111/1471-0528.14640 


[6] Eltoukhi, Heba M et al. “The health disparities of uterine fibroid tumors for African American women: a public health issue.” American journal of obstetrics and gynecology vol. 210,3 (2014): 194-9. doi:10.1016/j.ajog.2013.08.008

 

[7] Pavone, Dora et al. “Epidemiology and Risk Factors of Uterine Fibroids.” Best practice & research. Clinical obstetrics & gynaecology vol. 46 (2018): 3-11. doi:10.1016/j.bpobgyn.2017.09.004 


[8] Baird, Donna Day et al. “Vitamin d and the risk of uterine fibroids.” Epidemiology (Cambridge, Mass.) vol. 24,3 (2013): 447-53. doi:10.1097/EDE.0b013e31828acca0 


[9] Palheta, Michel Santos et al. “Reporting of uterine fibroids on ultrasound examinations: an illustrated report template focused on surgical planning.” Radiologia brasileira vol. 56,2 (2023): 86-94. doi:10.1590/0100-3984.2022.0048 


[10] De La Cruz, Maria Syl D, and Edward M Buchanan. “Uterine Fibroids: Diagnosis and Treatment.” American family physician vol. 95,2 (2017): 100-107. 


[11] Christoffel, Ladina et al. “Transcervical Radiofrequency Ablation of Uterine Fibroids Global Registry (SAGE): Study Protocol and Preliminary Results.” Medical devices (Auckland, N.Z.) vol. 14 77-84. 3 Mar. 2021, doi:10.2147/MDER.S301166 


[12] Gupta, Janesh K et al. “Uterine artery embolization for symptomatic uterine fibroids.” The Cochrane database of systematic reviews ,5 CD005073. 16 May. 2012, doi:10.1002/14651858.CD005073.pub3 


[13] Milic, Andrea et al. “Laparoscopic ultrasound-guided radiofrequency ablation of uterine fibroids.” Cardiovascular and interventional radiology vol. 29,4 (2006): 694-8. doi:10.1007/s00270-005-0045-9 


[14] Guarnaccia, M M, and M S Rein. “Traditional surgical approaches to uterine fibroids: abdominal myomectomy and hysterectomy.” Clinical obstetrics and gynecology vol. 44,2 (2001): 385-400. doi:10.1097/00003081-200106000-00024 


[15] Single Arm Study Using the Symphony -- MRI Guided Focused Ultrasound System for the Treatment of Leiomyomas (HIFUSB). ClinicalTrials.gov identifier: NCT03323905. Updated July 9, 2024. Accessed July11, 2024 https://clinicaltrials.gov/study/NCT03323905

bottom of page