Amenorrhea is the absence of a menstrual period.
Amenorrhea is sometimes categorized as primary or secondary.
- Primary amenorrhea describes a young woman who has not had a period by age 16.
- Secondary amenorrhea occurs when a woman who once had regular periods experiences an absence of more than three cycles. Secondary amenorrhea may occur during pregnancy.
Secondary amenorrhea is more common than primary amenorrhea.
Having regular periods is an important sign of overall health. Missing a period, when not caused by pregnancy, breastfeeding, or menopause, is generally a sign of another health problem. If you miss your period, talk to your health care provider about possible causes, including pregnancy.
Symptoms of Amenorrhea
Missing a period is the main sign of amenorrhea. Depending on the cause, a woman might have other signs or symptoms as well, such as:
- Excess facial hair;
- Hair loss;
- Lack of breast development;
- Milky discharge from the breasts;
- Vision changes;
Risk Factors for Amenorrhea
According to the American Society for Reproductive Medicine, amenorrhea that is not caused by pregnancy, breastfeeding, or menopause occurs in 3% to 4% of women during their lifetime.
The risk factors for amenorrhea include:
- Excessive exercise;
- Eating disorders such as anorexia nervosa;
- A family history of amenorrhea or early menopause;
- Certain changes to the FMR1 gene, which also causes fragile X syndrome3;
Causes of Amenorrhea
Amenorrhea can happen for many reasons. It most often occurs as a natural part of life, such as during pregnancy or breastfeeding, but it can also signal a more serious condition.
Causes of primary amenorrhea
There are three main causes of primary amenorrhea:
- Chromosomal or genetic abnormalities can cause the ovaries to stop functioning normally. Turner syndrome, a condition caused by a partially or completely missing X chromosome, and androgen insensitivity syndrome, often characterized by high levels of testosterone, are two examples of genetic abnormalities that can delay or disrupt menstruation.
- Hypothalamic or pituitary problems in the brain and physical problems such as problems with reproductive organs can prevent periods from starting.
- Excessive exercise, eating disorders, extreme physical or psychological stress, or a combination of these factors can delay the onset of menstruation.
Causes of secondary amenorrhea
Secondary amenorrhea can result from various causes, such as:
- Natural causes.
- Pregnancy is the most common cause.
- Other natural causes include breastfeeding and menopause.
- Medications and therapies.
- Certain birth control pills, injectable contraceptives, and intrauterine devices (IUDs) can cause amenorrhea. It can take a few months after stopping birth control for the menstrual cycle to restart and become regular.
- Some medications, including certain antidepressants and blood pressure medications, can increase the levels of a hormone that prevents ovulation and the menstrual cycle.
- Chemotherapy and radiation treatments for hematologic cancer (including blood, bone marrow, and lymph nodes) and breast or gynecologic cancer can destroy estrogen-producing cells and eggs in the ovaries, leading to amenorrhea. The resulting amenorrhea may be short-term, especially in younger women.
- Sometimes scar tissue can build up in the lining of the uterus, preventing the normal shedding of the uterine lining in the menstrual cycle. This scarring sometimes occurs after a dilation and curettage (D&C), a procedure in which tissue is removed from the uterus to diagnose or treat heavy bleeding or to clear the uterine lining after a miscarriage cesarean section, or treatment for uterine fibroids.
- Hypothalamic amenorrhea. This condition occurs when the hypothalamus, a gland in the brain that regulates body processes, slows or stops releasing gonadotropin-releasing hormone (GnRH), the hormone that starts the menstrual cycle. Common characteristics of women with hypothalamic amenorrhea include:
- Low body weight
- Low percentage of body fat
- Very low intake of calories or fat
- Emotional stress
- Strenuous exercise that burns more calories than are taken in through food
- Deficiency of leptin, a protein hormone that regulates appetite and metabolism
- Some medical conditions or illnesses
- Gynecological conditions. Unbalanced hormone levels are common features of certain conditions that have secondary amenorrhea as a main symptom. These can include:
- Polycystic ovary syndrome (PCOS). PCOS occurs when a woman's body produces more androgens (a type of hormone) than normal. High levels of androgens can cause fluid-filled sacs or cysts to grow in the ovaries, interfering with the release of eggs (ovulation). Most women with PCOS either have amenorrhea or experience irregular periods, called oligomenorrhea.
- Fragile X-associated primary ovarian insufficiency (FXPOI). The term FXPOI describes a condition in which a woman's ovaries stop functioning before normal menopause, sometimes around age 40. FXPOI results from certain changes to a gene on the X chromosome. As many as 10% of women who seek treatment for amenorrhea have FXPO.
- Thyroid problems. The thyroid is a small butterfly-shaped gland at the base of the neck, just below the Adam's apple. The thyroid produces hormones that control metabolism and play a role in puberty and menstruation. A thyroid gland that is overactive (called hyperthyroidism) or underactive (hypothyroidism) can cause menstrual irregularities, including amenorrhea.
- Pituitary tumor. Noncancerous tumors in the pituitary gland in the brain, which regulates the production of hormones that affect many body functions, including metabolism and the reproductive cycle, can interfere with the body's hormonal regulation of menstruation.
Diagnosis of Amenorrhea
Your health care provider will usually ask a series of questions to begin diagnosing amenorrhea, including:
- How old were you when you started your period?
- What are your menstrual cycles like? (What is the typical length of your cycle? How heavy or light are your periods?)
- Are you sexually active?
- Could you be pregnant?
- Have you gained or lost weight recently?
- How often and how much do you exercise?
If you are older than 16 and have never had a period, your health care provider will do a thorough medical history and physical exam, including a pelvic exam, to see if you are experiencing other signs of puberty. Depending on the findings and on your answers to the questions above, other tests may be ordered to determine the cause of your amenorrhea.
If you are sexually active, your health care provider will likely order a pregnancy test. He or she will also perform a complete physical exam, including a pelvic exam.
You should contact your health care provider as soon as possible after you miss a period.
Other tests you may need include:
- Thyroid function test. This test measures the amount of thyroid-stimulating hormone (TSH) in your blood, which can help determine if your thyroid is working properly. A thyroid gland that is overactive (hyperthyroidism) or underactive (hypothyroidism) can cause menstrual irregularities, including amenorrhea.
- Ovary function test. This test measures the amount of follicle-stimulating hormone (FSH) or luteinizing hormone (LH)—hormones made by the pituitary gland in your blood to determine if your ovaries are working properly. Your health care provider may also evaluate the level of anti-Mullerian hormone (AMH), which is produced by the ovarian follicles. Higher levels of AMH may be a symptom of PCOS.
- Androgen test. Androgens are sometimes called "male hormones" because men need higher levels of these hormones than woman do for overall health. However, both men and women need androgens to stay healthy. Your health care provider may want to check the level of male androgens in your blood.
- Hormone challenge test. With this test, you will take a hormonal medication for seven to 10 days in an effort to trigger a menstrual cycle. Results from the test can tell your health care provider whether your periods have stopped because of a lack of estrogen.
- Screening for a permutation of the FMR1 gene. Changes in this gene can cause the ovaries to stop functioning properly, leading to amenorrhea.
- Chromosome evaluation. This test, also known as a karyotype, involves counting and evaluating the chromosomes from cells in the body to identify any missing, extra, or rearranged cells. Results from this evaluation can help determine the cause of the chromosomal abnormality causing primary or secondary amenorrhea.
- Ultrasound. This painless test uses sound waves to produce images of internal organs. This test can help determine if your reproductive organs are all present and shaped normally.
- Computed tomography (CT). CT scans combine many X-ray images taken from different directions to create cross-sectional views of internal structures. A CT scan can indicate whether your uterus, ovaries, and kidneys look normal.
- Magnetic resonance imaging (MRI). MRI uses radio waves with a strong magnetic field to produce detailed images of soft tissues within the body. Your health care provider may order an MRI to check for a pituitary tumor or to examine your reproductive organs.
- Hysteroscopy. In this procedure a thin, lighted camera is passed through your vagina and cervix to allow your health care provider to look at the inside of your uterus.
Your health care provider might use several of these tests to attempt to diagnose the cause of amenorrhea. In some cases, no specific cause for the amenorrhea can be found. This situation is called idiopathic amenorrhea.
Treatment of Amenorrhea
The treatment for amenorrhea depends on the underlying cause, as well as the health status and goals of the individual.
If primary or secondary amenorrhea is caused by lifestyle factors, your health care provider may suggest changes in the areas below:
- Weight. Being overweight or severely underweight can affect your menstrual cycle. Attaining and maintaining a healthy weight often helps balance hormone levels and restore your menstrual cycle.
- Stress. Assess the areas of stress in your life and reduce the things that are causing stress. If you can't decrease stress on your own, ask for help from family, friends, your health care provider, or a professional listener such as a counselor.
- Level of physical activity. You may need to change or adjust your physical activity level to help restart your menstrual cycle. Talk to your health care provider and your coach or trainer about how to train in a way that maintains your health and menstrual cycles.
Be aware of changes in your menstrual cycle and check with your health care provider if you have concerns. Keep a record of when your periods occur. Note the date your period starts, how long it lasts, and any problems you experience. The first day of bleeding is considered the first day of your menstrual cycle.
For primary amenorrhea, depending on your age and the results of the ovary function test, health care providers may recommend monitoring the symptoms over time. If an ovary function test shows low follicle-stimulating hormone (FSH) or luteinizing hormone (LH) levels, menstruation may just be delayed. In females with a family history of delayed menstruation, this kind of delay is common.
Primary amenorrhea caused by chromosomal or genetic problems may require surgery. Women with a genetic condition called 46, XY gonadal dysgenesis have one X and one Y chromosome, but their ovaries do not develop normally. This condition increases the risk for cancer developing in the ovaries. The gonads (ovaries) are often removed through laparoscopic surgery to prevent or reduce the risk of cancer.
Treatment for secondary amenorrhea, depending on the cause, may include medical or surgical treatments or a combination of the two.
Medical Treatments for Secondary Amenorrhea
Common medical treatments for secondary amenorrhea include:
- Birth control pills or other types of hormonal medication. Certain oral contraceptives may help restart the menstrual cycle.
- Medications to help relieve the symptoms of PCOS. Clomiphene citrate (CC) therapy is often prescribed to help trigger ovulatio
- Estrogen replacement therapy (ERT). ERT may help balance hormonal levels and restart the menstrual cycle in women with primary ovarian insufficiency (POI) or fragile X-associated primary ovarian insufficiency (FXPOI). Women with FXPOI often experience symptoms of menopause, such as hot flashes and night sweats. ERT replaces the estrogen a woman's body should be making naturally for a normal menstrual cycle. In addition, ERT may help women with FXPOI lower their risk for the bone disease osteoporosis. ERT can increase the risk for uterine cancer, so your health care provider may also prescribe progestin or progesterone to reduce this risk.
In general, medications are safe, but they can have side effects, some of which may be serious. You should discuss side effects and risks with your health care provider before deciding on any specific medical treatment.
Surgical Treatments for Secondary Amenorrhea:
Surgical treatment for amenorrhea is not common, but may be recommended in certain conditions. These include:
- Uterine scarring. This scarring sometimes occurs after removal of uterine fibroids, a cesarean section, or a dilation and curettage (D&C), a procedure in which tissue is removed from the uterus to diagnose or treat heavy bleeding or to clear the uterine lining after a miscarriage.6 Removal of the scar tissue during a procedure called a hysteroscopic resection can help restore the menstrual cycle.
- Pituitary tumor. Medications may be recommended to shrink the tumor. If this does not work, surgery may be necessary to remove the tumor. Pituitary tumors are not cancerous, but they can cause problems as they grow. Pituitary tumors can put pressure on surrounding blood vessels and nerves such as the optic nerve and may result in loss of vision.
Most of the time, pituitary tumors are removed through the nose and sinuses. Radiation therapy may be used to shrink the tumor, either in combination with surgery or, for those who cannot have surgery, by itself.
How does amenorrhea affect bone health?
An important part of the menstrual cycle is the production of the hormone estrogen. Estrogen also plays a role in bone health. If amenorrhea is caused by low estrogen or problems with estrogen production, a woman may be at risk for loss of bone mass.
Some common causes of estrogen deficiency are excessive exercise and eating disorders. These can have a negative effect on bone density. Adolescent girls in particular need a combination of calcium, vitamin D, and physical activity to build strong bones during this critical time. Years ago, researchers found that girls with amenorrhea who diet are at risk for low bone density and that this condition increases their risk for osteoporosis later in life.
Amenorrhea that results from fragile X-associated primary ovarian insufficiency (FXPOI) also increases the risk for osteoporosis. It is important to see your health care provider as early as possible to begin investigating the cause of amenorrhea. According to one study, two-thirds of adolescent girls who reported FXPOI also had osteopenia, an early stage of osteoporosis, at their first visit.
When should I talk to my health care provider about a missed period or several missed periods?
If you have had regular periods or if there is any chance you may be pregnant, check with your health care provider about a missed period right away.
If you are just beginning to menstruate, keep in mind that it may take several months for your menstrual cycle to become regular. As you age, the time from the beginning of one cycle to the beginning of the next will likely range from 21 to 35 days, but your periods should become more regular over time.
See your health care provider right away if:
- You have not started menstruating by the age of 16.
- You have not started menstruating within three years after you developed breasts, or if you have not started developing breasts by age 13.
- You have not had a period for more than three months.
- Your periods become very irregular after you previously had regular, monthly cycles.
Can I still get pregnant if I have amenorrhea?
Yes, you can still get pregnant even if you do not have regular periods. Although some of the conditions that cause amenorrhea can also contribute to infertility, there is still a chance for pregnancy.
In addition, certain medical treatments for amenorrhea can increase the chances of pregnancy. If you do not want to become pregnant and you have amenorrhea, you should use contraception to prevent pregnancy.
Some women believe that they cannot get pregnant if they are breastfeeding and they aren't having menstrual periods. Unless a woman has gone through menopause, there is always the chance that she could get pregnant. If you are breastfeeding and want to prevent pregnancy, you should use a form of birth control to do so.
Reference: National Institutes of Child Health and Human Development