Navigating the challenges that come with menopause can be overwhelming. While hormone therapy offers real benefits – relief from hot flashes, night sweats and vaginal dryness, and protection against fractures – it also has been linked to higher rates of breast cancer, stroke, blood clots in the legs and lungs, and heart disease in older women.
Dr. JoAnn E. Manson, MD, DrPH, is Chief of the Division of Preventive Medicine at Brigham and Women's Hospital. She also is author of Hot Flashes, Hormones, and Your Health: Breakthrough Findings to Help You Sail Through Menopause.
What are health factors that should be considered when making the decision about hormone therapy?
Dr. Manson: The key factor to consider is whether you have significant symptoms of menopause, such as moderate-to-severe hot flashes or night sweats that interfere with your sleep and impair your quality-of-life. Other factors to consider are your age, the amount of time since your final menstrual period, whether you are in good cardiovascular health, and your risk factors for breast cancer and osteoporosis.
Does hormone therapy increase breast cancer risk?
Dr. Manson: Many observational studies have suggested that there is an association between combination estrogen plus progestin and breast cancer, and that the risk of breast cancer increases with longer-term use (greater than four to five years).
These findings were confirmed in the Women’s Health Initiative (WHI) trial of combination estrogen-progestin, a large study of more than 16,000 healthy postmenopausal women aged 50 to 79 who were followed for an average of 5.6 years. In July 2002, this study (Brigham and Women’s Hospital was one of 40 study sites across the country) stopped prematurely because it showed that there was a slight increase of breast cancer risk in the women who took combination hormone therapy and that the overall risks outweighed the benefits. In contrast, estrogen-alone therapy (in women with hysterectomy) did not increase the risk of breast cancer over seven years, but observational studies suggest that breast cancer risk may increase with longer duration of use.
Is there an increased risk of cardiovascular disease?
Dr. Manson: Randomized clinical trials suggest that women at high risk of heart disease, or those at least 10 years past menopause, may have a small increased risk of heart attack with hormone therapy. These studies also suggest a slightly increased risk of stroke and blood clots from these hormones. As a result of these studies, hormone therapy is no longer prescribed for the express purpose of reducing the risk of cardiovascular disease. However, recent analyses from the WHI and other studies indicate that younger women who are recently menopausal may have more favorable effects from hormone therapy in terms of heart disease. These findings, together with the relatively low rates of adverse events in younger women, provide some reassurance for recently menopausal women who are considering hormone therapy for treatment of distressing menopausal symptoms.
Is short-term hormone therapy safe?
Dr. Manson: Hormone therapy is still an appropriate option for some – though not all – women. Estrogen is very effective for the treatment of moderate to severe menopausal symptoms, such as hot flashes or night sweats that are severe and frequent enough to disrupt sleep or quality-of-life. For newly menopausal women – whose final menstrual period took place five or fewer years ago – estrogen is likely safe to use on a short-term basis (ideally two to three years, and generally no more than five years). Mounting evidence suggests that hormone therapy does not adversely affect the risk of heart disease in younger women and may even confer heart benefits. With longer-term use, however, the risk of breast cancer becomes an important factor in the equation.
How should I make a decision about hormone therapy?
Dr. Manson: Estrogen use is very effective for the treatment of moderate to severe menopausal symptoms and, for many women close to menopause onset, is probably safe to use on a short-term basis. Although there is no magic formula for deciding whether or not to take hormone therapy, assessing your time since menopause and your personal risk of various diseases associated with hormone therapy is important. Your health history should be carefully discussed with your provider prior to starting hormone therapy.
To learn more, read Menopause: Commonly asked questions.
