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Abstract
Normal menstrual cycle is physiologically a very complex system and depend on three different organs, brain, ovary and the uterus. In order to have a normal menstrual cycle all these three organ need to work in perfect harmony. The median age of menarche is 12.9 years. The length of the normal menstrual cycle is highly variable. Normal menstrual cycles are characterized by a cycle length of 28 days (7 days), duration of flow of 4 days (2 days), and a blood loss of 40mL (20mL) . The mean volume of menstrual blood loss is 43mL, with a normal range of 20-80mL (Demir et al., 2000).
Menstrual irregularities can be caused by disturbance of the central gonadotropin-releasing hormone pulse generator as well as by significant weight loss, strenuous exercise, substantial changes in sleeping or eating habits, and severe stressors. Menstrual disturbances also occur with chronic diseases, such as poorly controlled diabetes mellitus; with genetic and congenital conditions, such as Turner syndrome (Diaz,etal., 2006).