Menstruation - absent

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Absence of menstruation (amenorrhea)

Menstruation - absent

Definition:

The absence of menstrual flow may be primary (menstruation fails to begin before age 16) or secondary (menstruation begins at the appropriate age, but later ceases for 6 or more months in the absence of normal causes such as pregnancy, lactation, or menopause).

Alternative Names:
Missed periods; Lack of menses; Periods - missed; Amenorrhea
Considerations:

Many perfectly normal females begin to menstruate later than most (the median age is 12.8).

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Pregnancy is often the first thought when a period is missed, but there are many reasons for having a late period.

The incidence of primary amenorrhea in the United States is less than 1%. The incidence of secondary amenorrhea (due to some cause other than pregnancy) is about 4% in the general population.

Increased risk is associated with extreme and prolonged exercise (particularly without adequate conditioning), body fat content less than 15% to 17%, extreme obesity, and taking hormonal supplements.

Symptoms associated with amenorrhea depend on the cause and may include the following:

Headache
Galactorrhea (breasts produce milk in a woman who is not pregnant or breast-feeding an infant)
Visual loss (in rare cases of pituitary tumor)
Marked weight gain or weight loss
Dry vagina
Increased hair growth in a "male" pattern (hirsutism)
Voice changes
Breast size changes

Common Causes:

PRIMARY AMENORRHEA

Normal delay of onset (up to age 16)
Lack of an opening in the membrane at the entrance of the vagina (hymen)
Drastic weight reduction
Congenital abnormalities of the genital system
Chromosomal abnormalities
Extreme obesity

SECONDARY AMENORRHEA

Pregnancy
Anxiety over pregnancy may cause a missed period, thereby increasing the anxiety even further
Drastic weight reduction
Vigorous athletics
Obesity
Emotional distress
Menopause (normal for women over age 45)
Endocrine disorders such as thyroid disease or pituitary disease/tumor
Drugs such as busulfan, chlorambucil, cyclophosphamide, oral contraceptives, phenothiazines, and non-oral contraceptives (such as Norplant and Depo-Provera)
Dilation and curettage (D and C)