Menstrual disorders are changes in normal period. Changes may be short or long term.

Menstrual Flow
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Normal Menstruation

Menstruation (period) is one part of a cycle in woman. A cycle is counted from the first day of bleeding to the first day of the next period. It is about 28 days, though 21-35 days is considered normal.

The cycle is run by a change in hormones. The rise and fall of hormones progesterone and estrogen cause a period to happen. When they rise they cause a thickening of the lining of the uterus. When they fall, the lining breaks down and passes out of the body. This is what causes bleeding. Bleeding often lasts from 3 to 5 days. However, 7 days is still considered normal.

This cycle will happen each month starting from about age 12 years old to an average age of 51 years old. The cycle normally only ends with pregnancy or menopause.

Heavy Menstrual Bleeding

Most women lose about 2 ounces of blood or less. Menorrhagia is a loss of more blood than normal. This happens if there is a high volume of blood or a period that lasts more than seven days. It can be caused by hormone changes or physical problems. The loss of blood can lead to anemia and other health problems.

Absence of Menstruation

Girls may not start to have their period when expected. This is called primary amenorrhea. It is diagnosed if one of the following happen:

  • No period by age 14 without growth of secondary factors like pubic hair and breast growth
  • No period by age 16 with or without growth of secondary factors like pubic hair and breast growth

Periods may also stop after they have already started. It is called secondary amenorrhea when a period is absent for at least three cycles. It may be caused by:

  • Pregnancy
  • Hormonal imbalances
  • Hypothyroidism
  • High levels of prolactin in the blood
  • Eating disorders
  • Mental health problems
  • Low or high body fat
  • Rapid weight loss
  • Too much exercise
  • Other health problems

Amenorrhea can lead to other problems such as a decrease in bone density. It can cause a higher risk of osteoporosis .

Other Types of Abnormal Bleeding

  • Metrorrhagia—mostly light bleeding in between periods. May be caused by hormone changes, birth control pill, or infections. It can also be caused by a growth on cervix, uterus or miscarriage.
  • Menometrorrhagia—is bleeding in between periods, then bleeding heavily during a period. May be caused by hormone problems.
  • Hypomenorrhea—is very light periods. Often found in female athletes. Can be caused by hormone changes from too much exercise and low weight. Can also be caused by anorexia.
  • Anovulatory cycle—a specific part of cycle does not happen. The egg is not released. It can change the cycle and how often the periods happens.

Less common problems include:

  • Polymenorrhea—too many periods close together (less than 21 days)
  • Oligomenorrhea—too few cycles (menses far apart)

Some causes of abnormal bleeding are:

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