Uterine fibroids are believed to be a hormone-driven condition. These noncancerous tumors are most common among perimenopausal women in their 40s and early 50s when estrogen levels are seen to surge.1,2 But new research is showing that estrogen isn’t the only culprit. A study published earlier this year in the Endocrine Society’s Journal of Clinical Endocrinology & Metabolism showed that women in midlife with both high levels of estrogen and testosterone are at a greater risk of developing fibroids.3
The 13-year long study looked at hormone levels of women participating in the Study of Women’s Health Across the Nation (SWAN).3 Led by Jason Y.Y. Wong, ScD, of Stanford University School of Medicine in Stanford, Calif., a team of researchers investigated the potential relationship of circulating estrogen and testosterone levels with the risk of developing fibroids.
Of the initial 3,240 women participating in the study, 43.6% completed nearly annual follow-up visits, which included testing for levels of estrogen and testosterone in the blood and asking whether they had been diagnosed with or treated with fibroids.
Results showed that 512 women reported a single occurrence of fibroids and 478 women had recurrent fibroids. In comparison to women with low levels of testosterone, the authors of the study found that women who had high testosterone levels were 1.33 times more likely to have a single incidence of fibroids. This risk was even greater in women with both high testosterone and estrogen levels. However, even though these same women were at a heightened risk for a single incidence of fibroids, they were less likely to experience a recurrence.
“Our research suggests women undergoing the menopausal transition who have higher testosterone levels have an increased risk of developing fibroids, particularly if they also have higher estrogen levels,” Dr. Wong said in an Endocrine Society press release. “This study is the first longitudinal investigation of the relationship between androgen and estrogen levels and the development of uterine fibroids.”4
Fibroids affect up to 80 percent of women by age 50, with African American women being at a higher risk.1 Not always symptomatic, fibroids can be the cause of heavy menstrual bleeding, pelvic pressure, painful intercourse, and incontinence and can take a major toll on a woman’s quality of life. Estrogen has been associated with the development of fibroids, while testosterone’s potential role has been unknown. Although testosterone is commonly seen as a male hormone, women also naturally produce small amounts.
“Our findings are particularly interesting because testosterone was previously unrecognized as a factor in the development of uterine fibroids,” added co-author Jennifer S. Lee, MD, PhD, of Stanford University School of Medicine and Veterans Affairs Palo Alto Health Care System in Palo Alto, CA. “The research opens up new lines of inquiry regarding how fibroids develop and how they are treated.”
ABOUT THE AUTHOR Alicia Armeli is a Health Freelance Writer, Registered Dietitian Nutritionist, and Certified Holistic Life Coach. She has master’s degrees in English Education and Nutrition. Through her writing, she empowers readers to live optimally by building awareness surrounding issues that impact health and wellbeing. In addition to writing, she enjoys singing, traveling abroad and volunteering in her community.
- US Department of Health and Human Services, Office on Women’s Health. (2015). Uterine fibroids fact sheet. Retrieved November 11, 2016, from https://www.womenshealth.gov/publications/our-publications/fact-sheet/uterine-fibroids.html
- The Centre for Menstrual Cycle and Ovulation Research. (2014). Perimenopause is a time of “Endogenous Ovarian Hyperstimulation.” Retrieved November 11, 2015, from http://www.cemcor.ubc.ca/resources/perimenopause-time-“endogenous-ovarian-hyperstimulation”
- Wong, J., Gold, E., Johnson, W., & Lee, J. (2016). Circulating sex hormones and risk of uterine fibroids: Study of Women’s Health Across the Nation (SWAN). The Journal of Clinical Endocrinology & Metabolism, 101(1): 123-130. doi: 10.1210/jc.2015-2935. https://www.ncbi.nlm.nih.gov/pubmed/26670127
- Endocrine Society. (2015). Elevated Testosterone Levels May Raise Risk of Uterine Fibroids. Retrieved November 12, 2016, from https://www.endocrine.org/news-room/press-release-archives/2015/elevated-testosterone-levels-may-raise-risk-of-uterine-fibroids