What causes stomach cramps during your period?

Is it diet related, or too much of a hormone or something?What causes stomach cramps during your period?
I had the same question once, for 28 days your womb gets ready to conceive when it doesnt it gets rid of everything hence the blood. To get rid of it, it has to push out like contractions to give birth. Some people say that women who experience a lot pain during their period will feel a lot of pain while giving birth, and women who experience little or no pain will give birth less painfully.
menstrual or stomach? menstrual is caused by the uterine walls contracting to expel the blood lining.
if it's your stomach that's different then "period" cramps - those are from the uterus - shedding all the stuff that it gets rid of
Each month, the inner lining of the uterus (the endometrium) builds up in preparation for a possible pregnancy. If the egg is not fertilized by a sperm, the current lining of the uterus is no longer needed. The woman's estrogen and progesterone hormone levels decline and the lining of the uterus becomes swollen and dies. It is then shed and will be replaced by a new lining in the next monthly cycle.
When the old uterine lining begins to break down, molecular compounds called prostaglandins are released. These compounds, specifically prostaglandin F2alpha (PGF2alpha), cause the muscles of the uterus to contract. When the uterine muscles contract, they constrict the blood supply (vasoconstriction) to the endometrium. This contraction blocks the delivery of oxygen to the tissue of the endometrium which, in turn, breaks down and dies. After the death of this tissue, the uterine contractions literally squeeze the old endometrial tissue through the cervix and out of the body by way of the vagina.