What are the real risks of using HRT?
For years, hormone replacement therapy - commonly called HRT - has been prescribed for menopausal women to relieve symptoms like vaginal dryness and hot flashes. It was also shown to help prevent life-threatening diseases like osteoporosis, uterine cancer, and heart disease. Recent research, however, has investigated the relationship between HRT and breast cancer risk. Despite its positives, HRT substantially increases a woman’s risk of breast cancer.
Multiple Risk Factors Including Use of HRT
Hormone replacement therapy is more or less exactly what it sounds like: medically replacing estrogen and progesterone, hormones that women’s bodies no longer produce after menopause. HRT can mean a combination of estrogen or progesterone (which is called progestin when it is made synthetically), or just estrogen by itself, depending on each woman’s need.
Most women take combined therapy to help with multiple symptoms of menopause and to decrease risk of uterine cancer. Women who have had hysterectomies, though, do not require progestin and hence can take estrogen-only therapy. Research has found that estrogen-only therapy does not increase breast cancer risk in menopausal women.
When a woman takes combined hormone therapy, there is a significant link between HRT and breast cancer risk, leading researchers to believe that progestin may be the cause of this increased risk, not estrogen.
Combined HRT increases breast cancer risk by about 5-6%, on average. In terms of numbers, this means that if ten thousand women took HRT, eight more women would develop breast cancer than if they had not taken HRT. In women who had taken HRT for a long time, the risk was even greater. Increased exposure to hormones increased breast cancer risk. Additionally, women taking HRT were also more likely to have advanced-stage cancer show up on mammograms, as well as other breast irregularities because of denser breast tissue.
The good news is that this increased breast cancer risk caused by combined estrogen and progestin HRT is not permanent. Within five years after stopping hormone therapy, a woman’s risk of breast cancer returns to what it would have been before she began HRT.
HRT is not the only factor that affects a woman’s risk of breast cancer. The combination of estrogen and progestin has an undeniable across-the-board effect on a woman’s likelihood of developing cancer but genetics, environment, and health also play large roles in the development of the disease. Although hormone therapy has helped many women conquer menopausal symptoms, its popularity has declined substantially since its link to breast cancer was discovered. Some women still use HRT for short periods of time, but few use it on a long term basis, as was common a few years ago.
The sobering relationship between combined HRT and breast cancer risk has led doctors to carefully reconsider prescribing hormone therapy. Ten years ago, the therapy was routine and doctors encouraged vast numbers of women to take hormone therapy not only to ease symptoms but to protect against other diseases. In retrospect, doctors may have actually further endangered women’s lives, against their best intentions.
Women considering hormone replacement therapy should talk to their doctors to make sure they have all the information they need to make an informed decision. It is also important to keep up with their monthly breast self-examinations and annual mammograms in order to manage the risk of breast cancer.