Fibroids, also known as leiomyomas, are estrogen-dependent. As a result, they typically grow and present symptoms during a woman’s reproductive years, when the ovaries are active. Once the ovaries stop naturally producing estradiol (estrogen)—usually in her mid-50’s— a woman is said to have entered menopause. Logically, the drop in estrogen production that occurs in menopause would cause any uterine fibroids to gradually shrink, and this is typically the case. Fibroids and their accompanying symptoms often diminish after menopause. But what if they don’t?
There are a number of reasons why a woman would continue to have difficulty with a fibroid tumor during this stage of her life: stimulation from exogenous estrogen production (i.e. hormone replacement therapy), cancerous tumors, or malignant uterine/fibroid changes are a few possible causes.
Hormone replacement is commonly prescribed for menopausal women to reduce the uncomfortable symptoms that result from estrogen-deficiency, including hot flushes, vaginal dryness, mood fluctuations, and reduced desire for sex. Estrogen deficiency can also compromise bone health, increasing the risk of fractures; adding supplemental estrogens back into the body can help maintain a woman’s bone strength after menopause.
Replacing estrogen with hormone therapy can drastically increase the quality of life for many women in menopause. However, the risks of hormone replacement can sometimes outweigh the benefits, the recurrence or worsening of fibroid symptoms being one example. Dr. Donald Galen, OB-GYN and former Surgical Director at the Reproductive Science Center of the San Francisco Bay Area explains, “if fibroids are present, the addition of estrogens will generally stimulate fibroid growth, or minimize fibroid regression which otherwise would occur during natural menopause.” A study by Lamminen et al. that compared the activity of fibroids in pre- and post-menopausal women found just that: proliferative activity was low in the post-menopausal subjects who weren’t receiving hormone replacement, whereas those women who were receiving hormones had “fibroid proliferative activity equal to premenopausal women”. Dr. Galen also advises patients of other risks related to hormone therapy, as well. He explains, “estrogen can increase health risks, such as an increased risk of blood clots, increased risk of breast hyperplasia/cancer, and increased risk of endometrial hyperplasia and/or endometrial cancer.”
Hormone replacement therapy isn’t the only reason women see a persistence in fibroid symptoms after menopause. Malignant changes in existing fibroids or the emergence of new, cancerous tumors (“neoplasia”) on the uterus or reproductive organs can produce symptoms like those of benign leiomyomas. Dr. Galen advises, “as a precaution, any woman with an increase in uterine growth/size and/or post-menopausal uterine bleeding should be evaluated to rule-out malignant uterine/fibroid changes.”
Burbank, Fred. Fibroids, Menstruation, Childbirth and Evolution: The Fascinating Story of Uterine Blood Vessels. Tucson, AZ: Wheatmark, 2009. 93. Print.
Lamminen, S. et al.”Proliferative activity of human uterine leiomyomacells as measured by automatic image analysis”,Gynecologic and Obstetetric Investigation. 1992; 34:111-114