Amenorrhea can be healthy and natural. During pregnancy, menstruation stops. It also ceases for many women while they are breastfeeding. Around the age of 50 years, periods stop altogether. However, it can also indicate a health problem.
Types of amenorrhea
A range of problems can cause menstruation to stop.
Amenorrhea is generally divided into two types:
In primary amenorrhea, menstruation does not start during puberty. If a young woman is developing normally but does not start her periods by the age of 15 years, she should see a physician. If a young woman of 13 years does not yet have any signs of starting puberty, she too should seek medical advice.
Primary amenorrhea is rare. In the United States, the prevalence is less than 0.1 percent.
In secondary amenorrhea, a woman's periods start, but then they cease to occur. This is normal during pregnancy or lactation, but it may also mean that there is a problem. In the U.S., secondary amenorrhea is thought to affect around 4 percent of women during their lifetime.
Secondary amenorrhea is sometimes defined as an absence of menstruation for at least 6 months in a woman who previously had normal periods.
Causes of secondary amenorrhea
Menstruation may stop because of a gynecological disorder, serious illness, physical stress, or because the woman is severely underweight.
If a woman's body mass index (BMI) falls below 19, her risk of developing secondary amenorrhea increases significantly. Serious weight loss may be the result of a physical illness or an eating disorder.
Stringent exercise can cause secondary amenorrhea. It is common among competitive long-distance runners and professional ballet dancers.
Severe emotional upheaval or extreme stress can also cause a woman's periods to stop.
Some medications, such as progesterone-only contraceptives, and a number of psychiatric drugs may result in the absence of menstruation. Other medications that affect menstruation include:
Amenorrhea can also be a consequence of a long-term illness, such as polycystic ovary syndrome, or premature ovarian failure. Hypothyroidism, in which the thyroid gland is underactive, can also cause it. A pituitary tumor may interfere with periods.
Depending on the cause of amenorrhea, other symptoms may occur. These include:
Women who experience these symptoms should seek medical advice.
Another reason for amenorrhea may be a genetic condition that stops the ovaries from working properly, such as Turner syndrome.
The doctor will need to investigate to find out why menstruation has stopped.
Hypothalamic pituitary problems, or an underactive thyroid, can lead to a hormone imbalance. These could be due to a tumor, either benign or cancerous, in the pituitary gland. Amenorrhea can be a sign of an over- or under-active thyroid gland.
Malformations of the with reproductive organs can also impact menstruation. A Mullerian defect is when the uterus and fallopian tubes do not form as they should.
Sometimes a girl is born with a structural problem relating to the genitals. Occasionally, the uterus and fallopian tubes may be missing. There may be problems of fusion, in which the tubes do not come together correctly.
In Müllerian agenesis, or Mayer-Rokitansky-KusterHauser (MRKH) syndrome, a woman may have normal ovaries, breasts, and clitoris, but there may be no vaginal opening, and the cervix and uterus may not be properly formed.
In this case, reproductive development will not follow the normal pattern, and menstruation may not be possible. In some cases, the cycle appears normal, but the woman will have difficulty with sexual intercourse, and there is a higher chance of difficulties with pregnancy, including miscarriage and preterm birth.
A diagnosis for secondary amenorrhea will focus on the underlying cause of the problem. One missing period will not generally be a matter of concern. At this stage, a pregnancy test may be given.
In the following situations, investigation is considered appropriate:
- A woman has nine menstrual periods in a year, or a cycle length of 35 days or more
- A woman who normally has regular periods and then does not have any for 3 months
- A woman whose periods are normally irregular and then she does not have any for 6 months.
Before carrying out any tests, the physician may ask questions about:
- What age did menstruation start
- If the woman is sexually active, and if she could be pregnant
- Whether the patient lost or gained weight, and what kind of exercise routine she follows
- The patient's menstrual cycle, for example, the length of the cycle and whether bleeding is heavy or light.
A number of tests may then be done, depending on what the cause appears to be. The first test will probably be a pregnancy test. Other tests may include a thyroid function test, ovary function test, androgen, and other hormone tests.
Treatment for secondary amenorrhea depends on the underlying cause.
Extreme weight loss and excessive exercise can trigger amenorrhea.
If the absent periods are caused by lifestyle factors, such as excessive exercise, a change of exercise plan or adjusting the diet may help to stabilize the monthly cycle. If emotional or mental stress is a problem, psychological therapy may help.
A woman who has experienced excessive weight loss may need a professionally supervised weight gain regime. Those with some type of eating disorder will be referred to a psychiatrist and a nutritionist or dietitian.
Women whose menstruation stops because of an underactive thyroid may receive treatment with thyroxine, a thyroid hormone. If a woman is overweight due to polycystic ovary syndrome, she may be advised to lose weight.
Periods may come back if a patient with premature ovary failure receives hormone replacement therapy (HRT).
If a girl is born with incomplete or malformed reproductive organs, surgery may be needed, although this does not guarantee that she will have normal menstrual cycles.
If menstruation does not return, it may be that the woman is experiencing early menopause. Most women begin their menopause around the age of 50, but in some women it can start as early as 40 years. Family history can affect this. Women who start their menopause early are at greater risk of osteoporosis. Medical advice should be sought.