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The absence of menstrual periods is called amenorrhea. Primary amenorrhea is the failure to start having a period by the age of 16. Secondary amenorrhea is more common and refers to either the temporary or permanent ending of periods in a woman who has menstruated normally in the past. Many women miss a period occasionally. Amenorrhea occurs if a woman misses three or more periods in a row.


The absence of menstrual periods is a symptom, not a disease. While the average age that menstruation begins is 12, the range varies. The incidence of primary amenorrhea in the United States is just 2.5%.
Some female athletes who participate in rowing, long distance running, and cycling, may notice a few missed periods. Women athletes at a particular risk for developing amenorrhea include ballerinas and gymnasts, who typically exercise strenuously and eat poorly.

Causes and symptoms

Amenorrhea can have many causes. Primary amenorrhea can be the result of hormonal imbalances, psychiatric disorders, eating disorders, malnutrition, excessive thinness or fatness, rapid weight loss, body fat content too low, and excessive physical conditioning. Intense physical training prior to puberty can delay menarche (the onset of menstruation). Every year of training can delay menarche for up to five months. Some medications such as anti-depressants, tranquilizers, steroids, and heroin can induce amenorrhea.

Primary amenorrhea

However, the main cause is a delay in the beginning of puberty either from natural reasons (such as heredity or poor nutrition) or because of a problem in the endocrine system, such as a pituitary tumor or hypothyroidism. An obstructed flow tract or inflammation in the uterus may be the presenting indications of an underlying metabolic, endocrine, congenital or gynecological disorder.
Typical causes of primary amenorrhea include:
  • excessive physical activity
  • drastic weight loss (such as occurs in anorexia or bulimia)
  • extreme obesity
  • drugs (antidepressants or tranquilizers)
  • chronic illness
  • turner's syndrome. (A chromosomal problem in place at birth, relevant only in cases of primary amenorrhea)
  • the absence of a vagina or a uterus
  • imperforate hymen (lack of an opening to allow the menstrual blood through)

Secondary amenorrhea

Some of the causes of primary amenorrhea can also cause secondary amenorrhea—strenuous physical activity, excessive weight loss, use of antidepressants or tranquilizers, in particular. In adolescents, pregnancy and stress are two major causes. Missed periods are usually caused in adolescents by stress and changes in environment. Adolescents are especially prone to irregular periods with fevers, weight loss, changes in environment, or increased physical or athletic activity. However, any cessation of periods for four months should be evaluated.
The most common cause of seconardy amenorrhea is pregnancy. Also, a woman's periods may halt temporarily after she stops taking birth control pills. This temporary halt usually lasts only for a month or two, though in some cases it can last for a year or more. Secondary amenorrhea may also be related to hormonal problems related to stress, depression, anorexia nervosa or drugs, or it may be caused by any condition affecting the ovaries, such as a tumor. The cessation of menstruation also occurs permanently after menopause or a hysterectomy.


It may be difficult to find the cause of amenorrhea, but the exam should start with a pregnancy test; pregnancy needs to be ruled out whenever a woman's period is two to three weeks overdue. Androgen excess, estrogen deficiency, or other problems with the endocrine system need to be checked. Prolactin in the blood and the thyroid stimulating hormone (TSH) should also be checked.
The diagnosis usually includes a patient history and a physical exam (including a pelvic exam). If a woman has missed three or more periods in a row, a physician may recommend blood tests to measure hormone levels, a scan of the skull to rule out the possibility of a pituitary tumor, and ultrasound scans of the abdomen and pelvis to rule out a tumor of the adrenal gland or ovary.


Treatment of amenorrhea depends on the cause. Primary amenorrhea often requires no treatment, but it's always important to discover the cause of the problem in any case. Not all conditions can be treated, but any underlying condition that is treatable should be treated.
If a hormonal imbalance is the problem, progesterone for one to two weeks every month or two may correct the problem. With polycystic ovary syndrome, birth control pills are often prescribed. A pituitary tumor is treated with bromocriptine, a drug that reduces certain hormone (prolactin) secretions. Weight loss may bring on a period in an obese woman. Easing up on excessive exercise and eating a proper diet may bring on periods in teen athletes. In very rare cases, surgery may be needed for women with ovarian or uterine cysts.

Key terms

Hymen — Membrane that stretches across the opening of the vagina.
Hypothyroidism — Underactive thyroid gland.
Hysterectomy — Surgical removal of the uterus.
Turner's syndrome — A condition in which one female sex chromosome is missing.


Prolonged amenorrhea can lead to infertility and other medical problems such as osteoporosis (thinning of the bones). If the halt in the normal period is caused by stress or illness, periods should begin again when the stress passes or the illness is treated. Amenorrhea that occurs with discontinuing birth control pills usually go away within six to eight weeks, although it may take up to a year.
The prognosis for polycystic ovary disease depends on the severity of the symptoms and the treatment plan. Spironolactone, a drug that blocks the production of male hormones, can help in reducing body hair. If a woman wishes to become pregnant, treatment with clomiphene may be required or, on rare occasions, surgery on the ovaries.


Primary amenorrhea caused by a congenital condition cannot be prevented. In general, however, women should maintain a healthy diet, with plenty of exercise, rest, and not too much stress, avoiding smoking and substance abuse. Female athletes should be sure to eat a balanced diet and rest and exercise normally. However, many cases of amenorrhea cannot be prevented.



Hogg, Anne Cahill. "Breaking the Cycle: Often Confused and Frustrated, Sufferers of Amenorrhea Now have Better Treatment Options." American Fitness 15, no. 4 (July-August 1997): 30-4.


American College of Obstetricians and Gynecologists. 409 12th St., S.W., P.O. Box 96920, Washington, DC 20090-6920.
Federation of Feminist Women's Health Centers.1469 Humboldt Rd, Suite 200, Chico, CA 96928. (530) 891-1911.
National Women's Health Network. 514 10th St. NW, Suite 400, Washington, DC 20004. (202) 628-7814.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.


absence of the menses. adj., adj amenorrhe´al.Primary amenorrhea refers to absence of the onset of menstruation at puberty or before age 18; it may be caused by underdevelopment or malformation of the reproductive organs or by endocrine disturbances. When menstruation has begun and then ceases, the term secondary amenorrhea is used. The most common cause of this is pregnancy, but if that is excluded, there is usually a disturbance of the endocrine glands concerned with the menstrual process. General ill health, a change in climate or living conditions, emotional shock or, frequently, either the hope or fear of becoming pregnant can sometimes stop the menstrual flow.
dietary amenorrhea cessation of menstruation accompanying loss of weight due to dietary restriction, the loss of weight and of appetite being less extreme than in anorexia nervosa and unassociated with psychological problems.
hypogonadotropic amenorrhea cessation of menstruation due to failure to maintain a critical body fat-to-lean ratio, resulting in hypothalamic suppression; seen in women who engage in strenuous exercise, such as athletes, dancers, and those who are excessively weight conscious.
lactation amenorrhea absence of the menses in association with lactation.
nutritional amenorrhea dietary a.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


Absence or abnormal cessation of the menses.
[G. a- priv. + mēn, month, + rhoia, flow]
Farlex Partner Medical Dictionary © Farlex 2012


Abnormal suppression or absence of menstruation.

a·men′or·rhe′ic, a·men′or·rhe′al adj.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


Gynecology The absence or abnormal cessation of menses, which may be 1º–no menstrual period by age 16, or 2º–menses stops for ≥ 6 months in a ♀ in whom normal menstruation was established or for 3 normal intervals in a ♀ with oligomenorrhea Scope 1º amenorrhea affects 2.5% of US ♀; 2º amenorrhea affects 3% of the population; it is most common in Pts under extreme stress Impact Amenorrheic ♀ do not ovulate, which makes them inconceivable; amenorrhea accompanied by absence of estrogen is linked to genital atrophy and osteoporosis; amenorrhea with minimal estrogen is linked to endometrial hyperplasia; ♀ with 1º amenorrhea may suffer psychosocial and psychosexual problems. See Post-pill amenorrhea.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.


Absence or abnormal cessation of the menses.
Synonym(s): amenorrhoea.
[G. a- priv. + mēn, month, + rhoia, flow]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


Absence or abnormal cessation of the menses.
Synonym(s): amenorrhea.
[G. a- priv. + mēn, month, + rhoia, flow]
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
Frequency of different gynecological conditions was primary infertility 91 (39.74%), secondary infertility 61 (26.63%), oligomenorrhea 43 (18.78%) and secondary amenorrhea 34 (14.85%) (Fig.
JoAnn Pinkerton said, "Although more definitive research is needed, premenopausal women who need chemotherapy for lung cancer appear to have a similar risk of amenorrhea, early menopause, and loss of fertility as premenopausal women receiving chemotherapy for breast cancer and lymphoma."
Chemotherapy-induced amenorrhea (CIA) developed in 145 (57.5%) of 252 patients who received only chemotherapy without OST.
The literature states that amenorrhea occurs at the same frequency post-pill discontinuation as it does spontaneously (8); however, women are often very stressed when their menses do not immediately resume post discontinuation.
When the diagnosis of MRKH was delivered and explained to the patient and her mother, the patient reported regular bladder and bowel function and continued amenorrhea. The patient also reported suicidal ideation, but reported major improvements in quality of life after taking residence in a behavioral health rehabilitation facility and maintaining regular psychiatric appointments and medications.
Current evaluation of amenorrhea. Fertil Steril 2008;90 5 Suppl:S219-25.
However, the use of aripiprazole to resolve MARTA-induced amenorrhea has rarely been reported, especially in amenorrhea without hyperprolactinemia.
The Turner syndrome is caused by the absence of 1 set of genes from the short arm of 1 X chromosome and presents with characteristic physical abnormalities such as short stature, amenorrhea due to ovarian failure, retruded mandible, ptosis, low hair line, low-set ears, webbed necks, renal structural anomalies, and other congenital malformations usually without mental retardation.
Defining unmet need in postpartum women encounters the problem that many are wholly or partially protected by lactational amenorrhea or postnatal abstinence and thus have a reason to postpone contraception regardless of their future childbearing wishes.
Primary amenorrhea is the complete absence of menstruation.
Anorexia nervosa is a very serious but hidden disorder in which the person has a relentless pursuit of thinness, is unwilling to maintain a healthy weight, has distorted body image and intense fear of gaining weight, disturbed eating behavior, and, in girls, amenorrhea.