Amenorrhea is the absence of menstruation, often defined as missing one or more menstrual periods.

Primary amenorrhea refers to the absence of menstruation in someone who has not had a period by age 15. The most common causes of primary amenorrhea relate to hormone levels, although anatomical problems also can cause amenorrhea.

Secondary amenorrhea refers to the absence of three or more periods in a row by someone who has had periods in the past. Pregnancy is the most common cause of secondary amenorrhea, although problems with hormones also can cause secondary amenorrhea.

Symptoms

Depending on the cause of amenorrhea, a woman might experience other signs or symptoms along with the absence of periods, such as:

1. Milky nipple discharge
2. Hair loss
3. Headache
4. Vision changes
5. Excess facial hair
6. Pelvic pain
7. Acne

Causes

Amenorrhea can occur for a variety of reasons. Some are normal, while others may be a side effect of medication or a sign of a medical problem.

Natural Amenorrhea

During the normal course of life, you may experience amenorrhea for natural reasons, such as:

1. Pregnancy
2. Breastfeeding
3. Menopause

Contraceptives

Some people who take birth control pills (oral contraceptives) may not have periods. Even after stopping birth control pills, it may take some time before regular ovulation and menstruation return. Contraceptives that are injected or implanted also may cause amenorrhea, as can some types of intrauterine devices.

Medications

Certain medications can cause menstrual periods to stop, including some types of:

1. Antipsychotics
2. Cancer chemotherapy
3. Antidepressants
4. Blood pressure drugs
5. Allergy medications

Lifestyle factors

Sometimes lifestyle factors contribute to amenorrhea, for instance:

1. Low body weight:

   Excessively low body weight — about 10% under normal weight — interrupts many hormonal functions in the body, potentially halting ovulation. Women who have an eating disorder, such as anorexia or bulimia, often stop having periods because of these abnormal hormonal changes.

2. Excessive exercise:

   Women who participate in activities that require rigorous training, such as ballet, may find their menstrual cycles interrupted. Several factors combine to contribute to the loss of periods in athletes, including low body fat, stress, and high energy expenditure.

3. Stress:

   Mental stress can temporarily alter the functioning of your hypothalamus — an area of the brain that controls the hormones that regulate the menstrual cycle. Ovulation and menstruation may stop as a result. Regular menstrual periods usually resume after the stress decreases.

Hormonal Imbalance

Many types of medical problems can cause hormonal imbalance, including:

1. Polycystic Ovary Syndrome (PCOS):

   Causes relatively high and sustained levels of hormones, rather than the fluctuating levels seen in the normal menstrual cycle.

2. Thyroid Malfunction:

   An overactive thyroid gland (hyperthyroidism) or underactive thyroid gland (hypothyroidism) can cause menstrual irregularities, including amenorrhea.

3. Pituitary Tumor:

   A noncancerous (benign) tumor in the pituitary gland can interfere with the hormonal regulation of menstruation.

4. Premature Menopause:

   Menopause usually begins around age 50. But, for some women, the ovarian supply of eggs diminishes before age 40 and menstruation stops.

Structural Problems

Problems with the sexual organs themselves also can cause amenorrhea. Examples include:

1. Uterine Scarring:

   Asherman's syndrome, a condition in which scar tissue builds up in the lining of the uterus, can sometimes occur after a dilation and curettage (D&C), cesarean section, or treatment for uterine fibroids. Uterine scarring prevents the normal buildup and shedding of the uterine lining.

2. Lack of Reproductive Organs:

   Sometimes problems arise during fetal development that leads to missing parts of the reproductive system, such as the uterus, cervix, or vagina. Because the reproductive system didn't develop fully, menstrual cycles aren't possible later in life.

3. Structural Abnormality of The Vagina:

   Obstruction of the vagina may prevent visible menstrual bleeding. A membrane or wall may be present in the vagina that blocks the outflow of blood from the uterus and cervix.

Risk Factors

Factors that may increase your risk of amenorrhea include:

1. Family History:

   If other women in the family have experienced amenorrhea, then a woman may have inherited a predisposition for the problem.

2. Eating Disorders:

   If a woman has an eating disorder, such as anorexia or bulimia, she is at a higher risk of developing amenorrhea.

3. Athletic Training:

   Rigorous athletic training can increase your risk of amenorrhea.

4. History of Certain Gynecologic Procedures:

   If you've had a, especially related to pregnancy, or a procedure known as loop electrodiathermy excision procedure (LEEP), your risk of developing amenorrhea is higher.

Complications

The causes of amenorrhea can cause other problems as well. These include:

1. Infertility and Problems With Pregnancy:

   If a woman doesn't ovulate and doesn't have menstrual periods, she can't become pregnant. When a hormone imbalance is the cause of amenorrhea, this can also cause miscarriage or other problems with pregnancy.

2. Psychological Stress:

   Not having periods when her peers are having theirs can be stressful, especially for young people who are transitioning into adulthood.

3. Osteoporosis and Cardiovascular Disease:

   These two problems can be caused by not having enough estrogen. Osteoporosis is a weakening of the bones. Cardiovascular disease includes heart attack and problems with the blood vessels and heart muscle.

4. Pelvic Pain:

   If an anatomical problem is causing amenorrhea, it may also cause pain in the pelvic area.

Tests

A variety of blood tests may be necessary, including:

1. Pregnancy Test:

   This will probably be the first test the doctor suggests, to rule out or confirm a possible pregnancy.

2. Thyroid Function Test:

   Measuring the amount of thyroid-stimulating hormone (TSH) in the blood can determine if the thyroid is working properly.

3. Ovary Function Test:

   Measuring the amount of follicle-stimulating hormone (FSH) in your blood can determine if your ovaries are working properly.

4. Prolactin Test:

   Low levels of the hormone prolactin may be a sign of a pituitary gland tumor.

5. Male Hormone Test:

   If a woman is experiencing increased facial hair and a lowered voice, the doctor may want to check the level of male hormones in your blood.

Hormone Challenge Test

For this test, you take a hormonal medication for seven to 10 days to trigger menstrual bleeding. Results from this test can tell the doctor whether your periods have stopped due to a lack of estrogen.

Imaging Tests

Depending on the signs and symptoms, the doctor might recommend one or more imaging tests, including:

1. Ultrasound:

   This test uses sound waves to produce images of internal organs. If a woman has never had a period, the doctor may suggest an ultrasound test to check for any abnormalities in her reproductive organs.

2. Magnetic Resonance Imaging (MRI)

   Uses radio waves with a strong magnetic field to produce exceptionally detailed images of soft tissues within the body. The doctor may order for MRI to check for a pituitary tumor.

Scope Tests

If other testing reveals no specific cause, the doctor may recommend a hysteroscopy — a test in which a thin, lighted camera is passed through the vagina and cervix to look at the inside of the uterus.

More Information

• CT SCAN
• MRI
• ULTRASOUND

Treatment

Treatment depends on the underlying cause of amenorrhea. In some cases, birth control pills or other hormone therapies can restart the menstrual cycles. Amenorrhea caused by thyroid or pituitary disorders may be treated with medications. If a tumor or structural blockage is causing the problem, surgery may be necessary.

Lifestyle and home remedies

Some lifestyle factors — such as too much exercise or too little food — can cause amenorrhea, so strive for balance in work, recreation and rest. Assess areas of stress and conflict in life. If one can't decrease stress on own, ask for help from family, friends, or doctor.

Be aware of changes in the menstrual cycle and check with a doctor. Keep a record of periods that occur. Note the date of period starts, how long it lasts, and any troublesome symptoms experience.