Home > Medical Reference > Patient Education
Menopause - Introduction
Description
An in-depth report on the treatment of menopause-related symptoms.
Alternative Names
Estrogen; Hormone replacement therapy
Introduction:
The ovaries have 200,000 - 400,000 follicles, tiny sacks that contain the materials needed to produce mature eggs, or ova. The ovaries produce two major female hormones: estrogen and progesterone.
Estrogen. Estrogens have an effect on about 300 different tissues throughout a woman's body:
- They are essential for the reproductive process and the development of the female organs.
- Estrogens determine the characteristic female distribution of body fat on the hips and thighs, which develops during adolescence.
- They also are involved in tissues in the central nervous system (including the brain), the bones, the liver, and the urinary tract.
Estrogen has different forms:
- The most potent form is estradiol.
- The other important, but less powerful, estrogens are estrone and estriol.
Most of the estrogens in the body are produced by the ovaries, but they can also be formed by other tissues, such as body fat, skin, and muscle.
Progesterone. Progesterone, the other major female hormone, is necessary for thickening and preparing the uterine lining for the fertilized egg.
Menopause and Perimenopause
As a woman ages, her supply of eggs declines. Menopause occurs naturally after a woman's ovaries fail to function and menstruation ends completely. (Menopause may also be induced if the ovaries are surgically removed.)
Perimenopause. Menopause does not occur suddenly. A period called perimenopause usually begins a few years before the last menstrual cycle. There are two stages in the transition:
- Early Stage. Perimenopause can begin in some women in their 30s, but most often it starts in women ages 40 - 44. It is marked by changes in menstrual flow and in the length of the cycle. There may be sudden surges in estrogen.
- Late Stage. The late stages of perimenopause usually occur when a woman is in her late 40s or early 50s. In the late stages of the menopausal transition, women begin missing the periods until they finally stop. About 6 months before menopause estrogen levels drop significantly. The fall in estrogen triggers the typical symptoms of vaginal dryness and hot flashes (which can last from half a year to more than 5 years after onset of menopause).
Menopause. Menopause is considered to have occurred when a woman has gone a full 12 months without a period. At the point at which menopause occurs, the following hormonal changes occur:
- Ovarian secretion of estrogen and progesterone ends.
- Once the ovaries have stopped producing estrogens, however, they still continue to produce small amounts of the male hormone testosterone, which can be converted to estrogen (estradiol) in body fat.
- In addition, the adrenal gland continues to produce androstenedione (a male hormone), which is converted to estrone and estradiol in the body fat.
Adrenal glands
Click the icon to see an image of the adrenal glands.
- The total estrogen produced after menopause, however, is far less than that produced during a woman's reproductive years.
The average age that women reach menopause is 51 years although it can occur as early as age 40 to as late as the early 60s. Women now have a life expectancy of more than 80 years. Currently, women can expect to live some 30 or 40 years of their life in the postmenopausal state.
Menopause is not a disease. However, many conditions are associated with estrogen depletion, including heart disease, osteoporosis, and other complications. Fortunately, effective treatments are available for these conditions.
In a number of studies, most women have reported menopause as a positive experience and have welcomed it with relief and as a sign of a new stage in life.
Resources
- www.menopause.org -- North American Menopause Society
- www.acog.org -- American College of Obstetricians and Gynecologists
- www.nia.nih.gov -- National Institute on Aging
- www.nih.gov/PHTindex.htm -- National Institutes of Health -- Menopausal Hormone Therapy Information
References
American College of Obstetricians and Gynecologists Committee on Gynecologic Practice. ACOG Committee Opinion No. 420, November 2008: hormone therapy and heart disease. Obstet Gynecol. 2008 Nov;112(5):1189-92.
Borrelli F, Ernst E. Black cohosh (Cimicifuga racemosa): a systematic review of adverse events. Am J Obstet Gynecol. 2008 Nov;199(5):455-66.
Beral V; Million Women Study Collaborators; Bull D, Green J, Reeves G. Ovarian cancer and hormone replacement therapy in the Million Women Study. Lancet. 2007 May 19;369(9574):1703-10.
Chlebowski RT, Kuller LH, Prentice RL, Stefanick ML, Manson JE, Gass M, et al. Breast cancer after use of estrogen plus progestin in postmenopausal women. N Engl J Med. 2009 Feb 5;360(6):573-87.
Col NF, Fairfield KM, Ewan-Whyte C, Miller H. In the clinic. Menopause. Ann Intern Med. 2009 Apr 7;150(7):ITC4-1-15.
Davis SR, Moreau M, Kroll R, Bouchard C, Panay N, Gass M, et al. Testosterone for low libido in postmenopausal women not taking estrogen. N Engl J Med. 2008 Nov 6;359(19):2005-17.
Farquhar C, Marjoribanks J, Lethaby A, Suckling JA, Lamberts Q. Long term hormone therapy for perimenopausal and postmenopausal women. Cochrane Database Syst Rev. 2009 Apr 15;(2):CD004143.
Furness S, Roberts H, Marjoribanks J, Lethaby A, Hickey M, Farquhar C. Hormone therapy in postmenopausal women and risk of endometrial hyperplasia. Cochrane Database Syst Rev. 2009 Apr 15;(2):CD000402.
Grodstein F, Manson JE, Stampfer MJ, Rexrode K. Postmenopausal hormone therapy and stroke: role of time since menopause and age at initiation of hormone therapy. Arch Intern Med. 2008 Apr 28;168(8):861-6.
Haimov-Kochman R, Barak-Glantz E, Arbel R, Leefsma M, Brzezinski A, Milwidsky A, et al. Gradual discontinuation of hormone therapy does not prevent the reappearance of climacteric symptoms: a randomized prospective study. Menopause. 2006 May-Jun;13(3):370-6.
Lethaby A, Hogervorst E, Richards M, Yesufu A, Yaffe K. Hormone replacement therapy for cognitive function in postmenopausal women. Cochrane Database Syst Rev. 2008 Jan 23;(1):CD003122.
Mosca L, Banka CL, Benjamin EJ, Berra K, Bushnell C, Dolor RJ, et al. Evidence-based guidelines for cardiovascular disease prevention in women: 2007 update. Circulation. 2007 Mar 20;115(11):1481-501.
Nelson HD. Menopause. Lancet. 2008 Mar 1;371(9614):760-70.
[No authors listed]. Herbal medicines for menopausal symptoms. Drug Ther Bull. 2009 Jan;47(1):2-6.
North American Menopause Society. Estrogen and progestogen use in peri- and postmenopausal women: March 2007 position statement of The North American Menopause Society. Menopause. 2007 Mar-Apr;14(2):168-82.
North American Menopause Society. The role of local vaginal estrogen for treatment of vaginal atrophy in postmenopausal women: 2007 position statement of The North American Menopause Society. Menopause. 2007 May-Jun;14(3 Pt 1):355-69.
Ravdin PM, Cronin KA, Howlader N, Berg CD, Chlebowski RT, Feuer EJ, et al. The decrease in breast-cancer incidence in 2003 in the United States. N Engl J Med. 2007 Apr 19;356(16):1670-4.
Reed SD, Newton KM, LaCroix AZ, Grothaus LC, Grieco VS, Ehrlich K. Vaginal, endometrial, and reproductive hormone findings: randomized, placebo-controlled trial of black cohosh, multibotanical herbs, and dietary soy for vasomotor symptoms: the Herbal Alternatives for Menopause (HALT) Study. Menopause. 2008 Jan-Feb;15(1):51-8.
Rossouw JE, Prentice RL, Manson JE, Wu L, Barad D, Barnabei VM, et al. Postmenopausal hormone therapy and risk of cardiovascular disease by age and years since menopause. JAMA. 2007 Apr 4;297(13):1465-77.
Tamimi RM, Hankinson SE, Chen WY, Rosner B, Colditz GA. Combined estrogen and testosterone use and risk of breast cancer in postmenopausal women. Arch Intern Med. 2006 Jul 24;166(14):1483-9.
Utian WH, Archer DF, Bachmann GA, Gallagher C, Grodstein F, Heiman JR, et al. Estrogen and progestogen use in postmenopausal women: July 2008 position statement of The North American Menopause Society. Menopause. 2008 Jul-Aug;15(4 Pt 1):584-602.
Wierman ME, Basson R, Davis SR, Khosla S, Miller KK, Rosner W, et al. Androgen therapy in women: an Endocrine Society Clinical Practice guideline. J Clin Endocrinol Metab. 2006 Oct;91(10):3697-710. Epub 2006 Oct 3.
- Reviewed last on: 8/25/2009
- Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
