Absence of Menstrual Periods

The disorders that cause primary amenorrhea are relatively uncommon, but the most common are

Genetic disorders include

Genetic disorders and birth defects that cause primary amenorrhea may not be noticed until puberty. These disorders cause only primary amenorrhea, not secondary.

Sometimes puberty is delayed in girls who do not have a disorder, and normal periods simply begin at a later age. Such delayed puberty may run in families.

The most common causes are

Pregnancy is the most common cause of amenorrhea among women of childbearing age.

The hypothalamus may malfunction for several reasons:

The pituitary gland may malfunction because

Antidepressants, antipsychotic drugs, oral contraceptives (sometimes), or certain other drugs can cause prolactin levels to increase, as can pituitary tumors and some other disorders.

The thyroid gland may cause amenorrhea if it is underactive (called hypothyroidism Hypothyroidism Hypothyroidism is underactivity of the thyroid gland that leads to inadequate production of thyroid hormones and a slowing of vital body functions. Facial expressions become dull, the voice... read more ) or overactive (called hyperthyroidism Hyperthyroidism Hyperthyroidism is overactivity of the thyroid gland that leads to high levels of thyroid hormones and speeding up of vital body functions. Graves disease is the most common cause of hyperthyroidism... read more ).

Less common causes of secondary amenorrhea include chronic disorders (particularly of the lungs, digestive tract, blood, kidneys, or liver), some autoimmune disorders, cancer, HIV infection, radiation therapy, head injuries, a hydatidiform mole (overgrowth of tissue from the placenta), Cushing syndrome, and malfunction of the adrenal glands. Scarring of the uterus (usually due to an infection or surgery), polyps, and fibroids can also cause secondary amenorrhea.

Genetic disorders, such as Fragile X syndrome Fragile X Syndrome Fragile X syndrome is a genetic abnormality on the X chromosome that leads to intellectual disability and behavior problems. Chromosomes are structures within cells that contain DNA and many... read more , may cause menstrual periods to stop early (premature menopause Premature Menopause Premature menopause is the permanent end of menstrual periods before age 40. It occurs because the ovaries no longer release eggs (ovulation) regularly and become less able to produce hormones... read more ).

Certain symptoms are cause for concern:

Girls should see a doctor within a few weeks if

Such girls may have primary amenorrhea.

If girls or women of childbearing age have had menstrual periods that have stopped, they should see a doctor if they have

Such women may have secondary amenorrhea. Doctors always do a pregnancy test when they evaluate women for secondary amenorrhea. Women may wish to do a home pregnancy test before they see the doctor.

Doctors first ask about the medical history, including the menstrual history. Doctors then do a physical examination. What they find during the history and physical examination often suggests a cause of amenorrhea and the tests that may need to be done (see table Some Causes and Features of Amenorrhea Some Causes and Features of Amenorrhea ).

For the menstrual history, doctors determine whether amenorrhea is primary or secondary by asking the girl or woman whether she has ever had a menstrual period. If she has, she is asked how old she was when the periods started and when the last period occurred. She is also asked to describe the periods:

If a girl has never had a period, doctors ask

This information enables doctors to rule out some causes. Information about delayed puberty and genetic disorders in family members can help doctors determine whether the cause is a genetic disorder.

Doctors ask about other symptoms that may suggest a cause and about use of drugs, exercise, eating habits, and other conditions that can cause amenorrhea.

During the physical examination, doctors determine whether secondary sexual characteristics have developed. A breast examination is done. A pelvic examination is done to determine whether genital organs are developing normally and to check for abnormalities in reproductive organs.

Doctors also check for symptoms that may suggest a cause such as

In girls or women of childbearing age, the first test is

If pregnancy is ruled out, other tests are done based on results of the examination and the suspected cause.

If girls have never had a period (primary amenorrhea) and have normal secondary sexual characteristics, testing begins with ultrasonography to check for birth defects that could block menstrual blood from leaving the uterus. If birth defects are unusual or difficult to identify, magnetic resonance imaging (MRI) may be done.

Tests are usually done in a certain order, and causes are identified or eliminated in the process. Whether additional tests are needed and which tests are done depend on results of the previous tests. Typical tests include

For hysteroscopy, doctors insert a thin viewing tube through the vagina and cervix to view the interior of the uterus. This procedure can be done in a doctor's office or in a hospital as an outpatient procedure.

For hysterosalpingography, x-rays are taken after a substance that can be seen on x-rays (a radiopaque contrast agent) is injected through the cervix into the uterus and fallopian tubes. Hysterosalpingography is usually done as an outpatient procedure in a hospital radiology suite.

If hormones trigger menstrual bleeding, the cause may be malfunction of the hormonal system that controls menstrual periods or premature menopause. If hormones do not trigger bleeding, the cause may be a disorder of the uterus or a structural abnormality preventing menstrual blood from flowing out.

If symptoms suggest a specific disorder, tests for that disorder may be done first. For example, if women have headaches and vision problems, MRI of the brain is done to check for a pituitary tumor.