April 2002

Understanding Menopause, Estrogen Replacement Therapy

In the 1800s, physicians referred to it as “the tragedy.” In the early 20th century, it was called “the change.” Today, it’s known as menopause — a natural life process that occurs when a woman’s ovaries stop functioning and her menstrual periods cease. On the average, menopause occurs around 50 years of age; in less than 1 percent of women, it occurs before 40.

“To understand menopause, it’s important to understand the functions of certain hormones,” UAMS Medical Center gynecologist Michael M. Miller, M.D., said. “The pituitary gland at the base of the brain secretes luteinizing hormone and follicle-stimulating hormone, which cause a woman’s ovaries to mature eggs and release sex hormones (estrogen and progesterone). Estrogen controls the development of the female sex characteristics and reproductive system. Progesterone prepares the lining of the uterus for implantation of a fertilized egg and readies the mammary glands to secrete milk. However, with age, a woman’s ovaries become less and less responsive to the luteinizing and follicle-stimulating hormones. As a result, secretion of estrogen and progesterone eventually stops, as does ovulation.”

In response to falling estrogen levels, about 75 percent of women experience “hot flashes” — which can last up to five minutes each and are characterized by red, warm skin and perspiration, sometimes followed by chills. Other possible symptoms are fatigue, irritability, insomnia, nervousness, night sweats, loss of bladder control, inflammation of the bladder or vagina, pain during sexual intercourse, occasional dizziness, tingling sensations, muscle and joint aches, and pounding heartbeat. Delayed consequences of menopause include the development of osteoporosis (severe thinning of the bones) and heart disease.

“Since estrogen preserves bone calcium, a decrease in the hormone’s level can result in osteoporosis,” Dr. Miller said. “During the first five years after menopause, 3 percent to 5 percent of bone is lost each year. After that, bone loss is 1 percent to 2 percent annually. Even minor injuries can lead to bone fractures — which can result in pain, interfere with quality of life and have been associated with an increased risk of death.”

To help prevent osteoporosis and relieve the various symptoms of menopause, gynecologists at UAMS Medical Center prescribe estrogen replacement therapy. Estrogen can be taken daily as a tablet or one to two times per week through a skin patch. The hormone is also available as a vaginal cream or ring when the primary reasons for its use are to prevent thinning of the vaginal lining and pain during intercourse. Up to 60 percent of women who are prescribed estrogen discontinue treatment within one year because of side effects — including blood clots, nausea, vomiting, headaches, breast discomfort and mood changes — or fears about breast cancer.

It has long been a concern that estrogen replacement might increase the risk of cancer. “Ongoing studies have yet to show any clear-cut association between this therapy and ovarian cancer, and increased risk of endometrial cancer (cancer of the lining of the uterus) in women who still have a uterus can be almost eliminated if they take a progesterone component with their estrogen,” Miller said. “Additionally, the increase in breast cancer incidence is more than offset by a reduced risk of dying from breast cancer and a reduced incidence of colon cancer. In summary, estrogen replacement therapy redistributes cancer risk somewhat, but there’s no overall increase in cancer risk and no increased risk of dying from cancer at any site in the body.”

However, estrogen replacement therapy is not usually prescribed for women who already have or have had breast cancer or advanced endometrial cancer. Normally, physicians also consider this type of therapy inappropriate for those who have genital bleeding of unknown cause, acute or chronic liver disease, a blood-clotting disorder or known heart disease.

“Recent studies have challenged the long-held belief that estrogen prevents heart disease,” Miller said. “Two studies have shown a small increase in heart disease during the first year of estrogen use. The long-term use of this hormone is now being studied to determine if it’s truly cardioprotective. The American College of Cardiology currently recommends that women who are at risk for heart disease discuss the use of aspirin therapy with their physicians.”

Alternative treatments for women who cannot or will not take estrogen include anti-anxiety drugs to reduce the discomfort of hot flashes and anti-depressants to help relieve depression, anxiety, irritability and insomnia. Long-term osteoporosis prevention and treatment can be achieved with other medications, including raloxifene and bisphosphonates. Raloxifene is an exciting drug that may lower the risk of breast cancer and heart disease in some patients. Bisphosphonates are nonhormonal medications that are very effective, but may have troubling side effects, such as irritation of the esophagus (the tube that connects the throat to the stomach).

To obtain more information about menopause, call the UAMS Medical Center Department of Obstetrics and Gynecology at (501) 686-6319.