Womens Health > Understanding Menstruation
Menstruation refers to a woman's monthly bleeding that arises because of shedding of the lining of uterus. Following the onset of menstruation, during each monthly cycle, the endometrium (lining of uterus) thickens under the action of estrogen and progesterone in preparation to nourish fetus (unborn baby) for the likely pregnancy. However, if pregnancy does not occurs, the endometrium is shed and it makes its way out through cervix (small opening in the uterus) and vagina along with blood and mucous.
A woman generally begins menstruating by the age 12-14 -usually a couple of years after the budding of breasts. Strenuous exercises, stress and diet may influence the onset of menstruation. In case you have not begun to menstruate by age 16, you should consult your caregiver.
Menstruation is a part of the menstrual cycle, which is 28 days long on an average. Day 1 of the cycle is the first day of your period. After your period is over, your ovaries secrete the hormone estrogen, which messages the endometrium to thicken. Follicle-stimulating hormone stimulates one of the eggs in your ovaries to mature. By the 14th day of your cycle, that egg leaves the ovaries and heads for the uterus. This is ovulation. After ovulation has occurred, your ovaries secrete another hormone, progesterone that prepares the uterus for possible pregnancy. If the sperm fertilizes that egg, pregnancy occurs. If fertilization does not occur, your body dissolves or absorbs the egg and the levels of estrogen and progesterone drop, stimulating the period to take place.
A period typically lasts for 5 days you can lose about 35-40 ml blood during each period. However, for the first 2-3 years after menstruation begins your period maybe irregular and may occur before or after it is scheduled, vary in length and the amount of blood you lose. It regularizes gradually.
Menstruation lasts up to the age 50-55 until you enter postmenopausal stage. Menopause, the stage immediately before post-menopause is another stage when your period may become irregular.