RISKS OF HRT

HRT is often not recommended for women who have any of the following conditions:

• Vaginal bleeding of an unknown cause;
• Suspected breast cancer or history of breast cancer;
• History of endometrial cancer or cancer of the uterus;
• Chronic disease of the liver; or
• History of venous thrombosis (blood clots in the veins or legs, or in the lung). This includes women who have had thrombosis or blood clots during pregnancy or when taking birth control pills. Although the risk of blood clots in women is very low, HRT increases the risk.

Short-term side effects:
Some women report side effects from taking HRT, including unusual vaginal discharge and bleeding, headaches, nausea, fluid retention and swollen breasts. Some women think HRT will make them gain weight while taking HRT, but research now shows this is not true. Some women do gain weight during menopause, but it is because their metabolism slows down as they age, and they many not be increasing their amount or level of physical activity. Short-term benefits or side effects should become apparent within weeks or months after treatment begins.

Long-term risks:
There is concern that HRT can increase the risk of some cancers. When estrogen is taken alone, it raises the risk of endometrial cancer (lining of the uterus). Adding progestin with estrogen (HRT) can dramatically reduce this risk. Progestin is added to prevent the overgrowth (or hyperplasia) of cells in the lining of the uterus, so women who still have an intact uterus are generally given this combined therapy.

There are some studies that suggest long term use of HRT (more than 10 years) increases the risk of breast cancer. While there is no definite proof that HRT increases the risk of breast cancer, two new studies that published in the winter of 2000, suggest that combined HRT (estrogen plus progestin) increases the risk of breast cancer more than taking estrogen alone. The National Cancer Institute (NCI) explains that in the first study, the risk for breast cancer among women who had used any form of HRT during the past 4 years was higher than the risk for women who did not use HRT. For women who had taken the combination HRT, however, the risk of breast cancer increased by 8 percent per year; compared to a one- percent increase for women taking estrogen alone. There was no increase in risk among women who had stopped using either type of HRT for 4 years or more. In the second study on HRT, the risk of developing breast cancer increased by 24 percent for every 5 years of use; compared to a 6 percent increase for estrogen-only therapy. Both studies reported that the increased risk of breast cancer associated with either ERT or HRT was higher in thin women. This is an interesting finding, since obesity is a risk factor for breast cancer.