Which women are at risk of uterine fibroids?
Fibroids usually grow in women of childbearing age. About one-third of U.S. women between ages 25 and 44 report having symptoms of fibroids.1 Affected African American women are more likely to have multiple fibroids.3 We don't know how many new cases of fibroids occur each year because some women with fibroids don't have any symptoms, while others might not seek medical care. It is likely that millions of U.S. women have fibroids at any one time.
There have been reports of rare cases in which young girls, who have not yet started their periods (pre-pubertal), had small fibroids. For African American women, fibroids typically develop at a younger age, grow larger, and cause more severe symptoms.2
Fibroids may shrink after menopause. However, research shows that they are more likely to shrink in postmenopausal white women than in premenopausal black women.
Several factors affect a woman's risk for having uterine fibroids.1
Factors that increase the risk of fibroids:
- Age older than 40 years
- African American race
- Family history of uterine fibroids
- High blood pressure
- No history of pregnancy
- Low levels of vitamin D
Factors that lower the risk of fibroids:
- Pregnancy (the risk decreases with increasing number of pregnancies)
- Long-term use of progestin-only birth control pills or oral contraceptives
- Use of the birth control shot (depot medroxyprogesterone acetate [DMPA], or Depo-Provera®)
- Hartmann, K. E., Birnbaum, H., Ben-Hamadi, R., Wu, E. Q., Farrell, M. H., Spalding, J., et al. (2006). Annual costs associated with diagnosis of uterine leiomyomata. Obstetrics and Gynecology, 108, 930–937. Retrieved April 11, 2012, from http://journals.lww.com/greenjournal/Fulltext/2006/10000/Self_Reported_Heavy_Bleeding_Associated_With.17.aspx
- Agency for Healthcare Research and Quality (AHRQ). (2007). Management of uterine fibroids: An update of the evidence (AHRQ Publication No. 07-E011). Retrieved December 8, 2011, from http://archive.ahrq.gov/downloads/pub/evidence/pdf/uterupdate/uterup.pdf (PDF - 343 KB)
- Laughlin, S. K., Baird, D. D., Savitz, D. A., Herring, A. H., & Hartmann, K. E. (2009). Prevalence of uterine leiomyomas in the first trimester of pregnancy: An ultrasound-screening study. Obstetrics and Gynecology, 113, 630–635. Retrieved April 11, 2012, from http://journals.lww.com/greenjournal/fulltext/2009/03000/prevalence_of_uterine_leiomyomas_in_the_first.10.aspx