Secondary amenorrhea

Alternative names:

amenorrhea - secondary

Definition:

A condition in which 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.

Causes, incidence, and risk factors:

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

Anxiety over a possible pregnancy may cause a missed period, thereby increasing the anxiety even further. Emotional distress from other causes can also cause a missed period. Drugs such as busulfan, chlorambucil, cyclophosphamide, oral contraceptives, phenothiazines, and non-oral contraceptives (such as Norplant and Depo-Provera) can all cause scanty or missed periods. Also, procedures such as a dilation and curettage (D&C) can cause a woman to miss a period or two.

Early appearance of menopause may account for some cases (menopause is normal for women over 45 years old).

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