Using Vaginal Estrogen Not Linked to High Breast Cancer Risk

Using Vaginal Estrogen Not Linked to High Breast Cancer Risk

Information from the Women's Health Initiative shows that postmenopausal women who use vaginal estrogen have the same risk of invasive breast cancer and other diseases as women who don't use vaginal estrogen.
Aug 23, 2017.This article is archived
We archive older articles so you can still read about past studies that led to today's standard of care.
 
An analysis of data collected as part of the Women’s Health Initiative (WHI) trial has found that postmenopausal women who use vaginal estrogen have the same risk of invasive breast cancer, stroke, blood clots, endometrial cancer, and colorectal cancer as women who don’t use vaginal estrogen.
The research is part of the very large Women’s Health Initiative Observational Study, commonly called the WHI. Overall, the study includes information from more than 161,608 postmenopausal women who were ages 50 to 79 when they joined from 1993 to 1998. The WHI wants to find any links between health, diet, and lifestyle factors and health problems such as cancer.
For this study, the researchers looked at information from 45,663 women who were ages 50 to 79. The women had not taken any type of hormone replacement therapy. Information about vaginal estrogen use was self-reported in the regular questionnaires sent out as part of the WHI. Information about the specific dose or type of vaginal estrogen -- ring, cream, or tablet, for example -- wasn’t reported.
For women who still had their uterus and used vaginal estrogen, the risk of:
  • invasive breast cancer
  • colorectal cancer
  • endometrial cancer
  • stroke
  • blood clots
was the same as it was for similar women who didn’t use vaginal estrogen.
Women who still had their uterus and used vaginal estrogen also had a lower risk of:
  • heart disease
  • breaking a bone
  • dying from any cause
Women who had had a hysterectomy and used vaginal estrogen also had the same risk of:
  • invasive breast cancer
  • colorectal cancer
  • endometrial cancer
  • stroke
  • blood clots
as similar women who didn’t use vaginal estrogen.
"Prior studies have never assessed the overall balance of risks and benefits of vaginal estrogen use, including cardiovascular events, cancers, and fractures," said lead author Carolyn Crandall, M.D., of UCLA. "Also, the use of oral forms of estrogen -- with and without progestogen -- have been linked with increased risk of cardiovascular events and cancer, but it was not known whether vaginal estrogen use was associated with these risks.
"The blood levels of estrogen that result from vaginal estrogen use are lower than those resulting from oral estrogen use, so we expected that associations with increased risk of cardiovascular disease and cancer might not be as pronounced with vaginal estrogen as those seen in studies of oral estrogen use. The results are reassuring that vaginal estrogen use is not associated with increased risk of cancer and cardiovascular disease," she added.
Menopausal side effects can dramatically reduce quality of life for some women. This study suggests that vaginal estrogen may be a good alternative to hormone replacement therapy. Many studies have shown a link between higher breast cancer risk and using hormone replacement therapy to treat menopausal symptoms. Women who’ve been diagnosed with breast cancer should NOT take any type of oral hormone replacement therapy.
In 2016, the American Congress of Obstetricians and Gynecologists concluded that women who’ve been diagnosed with breast cancer who are having troubling systems such as pain during sex may consider using vaginal estrogen at the lowest effective dose if nonhormonal moisturizers or lubricants don’t work.
If you’re having severe menopausal side effects, talk to your doctor about ALL your treatment options. Together you can decide if vaginal estrogen is right for your unique situation.
For more information on menopause and ways to manage side effects, visit the Breastcancer.org Managing Menopausal Symptoms pages.

— Last updated on July 31, 2022, 10:34 PM

Share your feedback
Help us learn how we can improve our research news coverage.