One particular study found that women taking estrogen had a 40 percent lower incidence of Alzheimer's disease. In addition, those women taking estrogen who did develop the disease seemed to have a milder form of the disease. However, it is too early to conclude that HRT can reduce the risk of Alzheimer's disease. Although for many women hormone replacement is very beneficial, it is not appropriate for every woman, nor is it free of potential risks. However, this risk may be counteracted with the addition of a synthetic progesterone, or progestin, which may actually enhance protection against uterine cancer.
Most women take both estrogen and progestin, in combination.
In addition, women who have undergone a hysterectomy and no longer have a uterus can take estrogen alone, since they are not at risk for uterine cancer. Some women experience breast tenderness and water retention, however, it is uncommon to have menstrual cramps. Other side effects of HRT may include headaches and nausea. Some women consider these to be a major drawback of HRT, while others see it as only a minor inconvenience. In the continuous method, a pill that contains both estrogen and progestin is taken daily.