Causes

Most girls begin menstruating between ages 9 and 18, with an average around 12 years old. Primary amenorrhea typically occurs when a girl is older than 15, if she has undergone other normal changes that occur during puberty. Primary amenorrhea may occur with or without other signs of puberty.

Being born with poorly formed genital or pelvic organs (missing uterus or vagina, vaginal septum, cervical stenosis, or imperforate hymen) can lead to primary amenorrhea.

Hormones play a big role in a woman's menstrual cycle. Hormone problems can occur when:

• Changes occur to the parts of the brain where hormones that help manage the menstrual cycle are produced
• The ovaries are not working correctly

These problems may be due to:

• Genetic defects
• Infections that occur in the womb or after birth
• Other birth defects
• Tumors

In many cases, the cause of primary amenorrhea is not known.

Conditions associated with primary amenorrhea include:

• Adrenogenital syndrome
• Anorexia
• Chromosomal abnormalities such as Turner syndrome or Sawyer syndrome
• Congenital heart disease (cyanotic)
• Congenital adrenal hyperplasia
• Craniopharyngioma
• Chronic (long-term) illnesses
• Cushing's disease
• Cystic fibrosis
• Gonadal dysgenesis
• Hypothyroidism and hyperthyroidism
• Hypogonadotropic hypogonadism
• Hyperprolactinemia
• Obesity
• Prader-Willi syndrome
• Polycystic ovarian disease
• Testicular feminization
• True hermaphroditism
• Tumors of the pituitary or adrenal glands
• Tumors of the ovaries

Symptoms

A female with amenorrhea will have no menstrual flow with or without other signs of puberty.

Exams and Tests

The doctor will perform a physical exam and ask questions about your medical history. A pregnancy test will be done.

Blood tests may include:

• Estradiol
• FSH
• LH
• Prolactin
• TSH
• T3 and T4

Other tests that may be done include:

• 17 hydroxyprogesterone
• Chromosome analysis
• Head CT
• Head MRI scan
• Laparoscopy
• Pelvic ultrasound
• Progesterone withdrawal
• Serum progresterone

Treatment

Treatment depends on the cause of the missing period. Primary amenorrhea caused by birth defects may require medications (hormones), surgery, or both.

If the amenorrhea is caused by a tumor in the brain (pituitary tumor):

• Medications may shrink certain types of tumors.
• Surgery to remove the tumor may also be necessary.
• Radiation therapy is usually only performed when other treatments have not worked.

If the condition is caused by a body-wide (systemic) disease, treatment of the disease may allow menstruation to begin.

If the amenorrhea is due to low weight because of anorexia or too much exercise, periods will often begin when the weight returns to normal or the exercise level is decreased.

Outlook (Prognosis)

Overall the outlook is good, depending on the cause of the amenorrhea. If the amenorrhea is caused by one of the following conditions, there is a good chance that it can be corrected with medication, lifestyle changes, or surgery:

• Adrenogenital syndrome
• Chronic illness
• Congenital heart disease
• Drastic weight reduction
• Hypogonadotropic hypogonadism
• Imperforate hymen or vaginal septum
• Malnutrition
• Normal delay of onset (up to age 14 or 15)
• Obesity
• Overactive thyroid

Periods are unlikely to start on their own if the amenorrhea was caused by one of the following conditions:

• Congenital abnormalities of the upper genital system
• Craniopharyngioma
• Cystic fibrosis
• Gonadal dysgenesis
• Prader-Willi syndrome
• Testicular feminization syndrome
• True hermaphroditism
• Turner syndrome (XO)

If the amenorrhea cannot be corrected, it is sometimes possible to create a menstrual-like situation (pseudomenstruation) with medications. Medicines can help you feel more like your friends or family, and will also protect the bones from becoming too thin (osteoporosis).

Possible Complications

• Emotional distress due to feeling different from friends or family, or worrying you might not be able to have children
• Osteoporosis and increased risk of fractures

When to Contact a Medical Professional

Call your health provider if your daughter is older than age 16 and has not yet begun menstruating, or if she is 14 and shows no other signs of puberty.

Alternative Names

Primary amenorrhea; No periods - primary; Absent periods - primary; Absent menses - primary; Absence of periods - primary

References

Lobo RA. Primary and secondary amenorrhea and precocious puberty: Etiology, diagnostic evaluation, management. In: Katz VL, Lentz GM, Lobo RA, Gershenson DM, eds. Comprehensive Gynecology. 5th ed. Philadelphia, Pa: Mosby Elsevier; 2007:chap 38.

Master-Hunter T, Heiman DL. Amenorrhea: evaluation and treatment. Am Fam Physician. 2006;73(8):1374-1382.

Update Date: 4/16/2012

Reviewed by: Susan Storck, MD, FACOG, Chief, Eastside Department of Obstetrics and Gynecology, Group Health Cooperative of Puget Sound, Redmond, Washington; Clinical Teaching Faculty, Department of Obstetrics and Gynecology, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.