Amenorrhea is the absence of menstruation. Primary amenorrhea is not considered to have occurred until a girl is beyond age 16, if she has undergone other normal changes that occur during puberty.

See also:

• Menstruation - absent
• Secondary amenorrhea

Most girls begin menstruating between ages 9 and 18, with an average around 12 years old. Primary amenorrhea is not considered to have occurred until a girl is beyond age 16, if she has undergone other normal changes that occur during puberty. Primary amenorrhea may occur with or without other signs of puberty.

There are many possible causes of primary amenorrhea:

• Adrenogenital syndrome
• 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
• Extreme weight loss
• Genital abnormalities present since birth (absence of the uterus or vagina, vaginal septum, cervical stenosis, imperforate hymen)
• Gonadal dysgenesis
• Hypoglycemia
• Hypothyroidism and hyperthyroidism
• Hypogonadotropic hypogonadism
• Hyperprolactinemia
• Malnutrition
• Obesity
• Prader-Willi syndrome
• Pregnancy
• Polycystic ovarian disease
• Testicular feminization
• True hermaphroditism
• Tumors of the pituitary or adrenal glands
• Tumors of the ovaries

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

The doctor will perform a physical exam and ask questions about the patient's medical history. A pregnancy test will be done.

Blood tests may include:

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

Other tests that may be done include:

• Progesterone withdrawal
• Chromosome analysis
• Urine chemistry, 17-ketosteroids
• Head CT
• Head MRI scan
• Pelvic ultrasound
• Laparoscopy

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), the tumor is usually treated with a drug called bromocriptine. 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.

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 possibility of correcting the amenorrhea through medication, lifestyle change, or surgery:

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

If the amenorrhea is caused by one of the following conditions, it is unlikely that the amenorrhea can be corrected by any method:

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

If the amenorrhea cannot be corrected, it is sometimes possible to create a menstrual-like situation (pseudomenstruation) with medications to help the young woman feel more like her friends or family.

Emotional distress or crisis about being different from friends or family and about possible inability to bear children can occur.

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.

Lobo RA. Abnormal Uterine Bleeding: Ovulatory and Anovulatory Dysfunctional Uterine Bleeding, Management of Acute and Chronic Excessive Bleeding. In: Katz VL, Lentz GM, Lobo RA, Gershenson DM. Comprehensive Gynecology. 5th ed. Philadelphia, Pa: Mosby Elsevier; 2007: chap. 37.

Master-Hunter T. Amenorrhea: Evaluation and Treatment. Am Fam Physician. Apr. 2006; 73(8): 1374-82.