Updated 16 April, 2007
Menstruation is an important indicator of both the function and the condition of the female reproductive organs.
It occurs due to the unique lining (mucus membrane) which covers or lines the cavity inside the womb.
This mucus membrane is so unique that it has its very own scientific name "The Endometrium".
The endometrium is where most of the menstrual syndromes, excessive and scanty menstruations and conditions such as endometriosis and adenomyosis originate from.
The understanding of normal menstruation will make it far easier to understand abnormal menstruation.
The effects of the contraception pill and contraception injections will also be easier to understand.
It will empower you with the knowledge to understand your own body better, to communicate with and understand your doctor's medical explanations better.
You will be in a better position to decide about your possible treatment options and their consequences.
The length of a menstrual cycle is calculated from the day it starts until it stops. It is usually 24 to 32 days with an average of 28 days. The bleeding lasts for 3-7 days. The color depends on the rate the bleeding occurs. Slow bleeding causes the color to become darker, even black. A slow rate causes the blood to take longer to reach the outside and old blood becomes darker . The womb forms substances that prevent clot formation and a normal menstruation is clot free. A fast rate prevent these anti clotting substances to be effective and clots form.
We will now explain the changes taking place in the womb during the normal female cycle. The changes occur in the endometrium, and the way in which these changes occur is the basic reason for the monthly menstrual bleeding. These changes are illustrated below.