Why do we get period pains?

why does it hurt around the ovaries during period time and stomach and sumtimes headache or backache?Why do we get period pains?
periods are the worst thing a woman can have beside birth it's why god invented Depo , :)mine were so bad I'd pass out and throw up blood
Menstrual cramps are caused by the normal contraction of the uterus. Like all muscles, the uterus contracts and relaxes. Most of the time women are unaware of these contractions. During menstruation uterine contractions are much stronger and it is these strong contractions that are most likely to be painful.
Uterine contractions are caused by prostaglandins. Prostaglandins are a natural substance made by the body; uterine prostaglandins cause uterine contractions. Strong uterine contractions cause the blood supply to the uterus to temporarily shutdown, depriving the uterine muscle of oxygen and setting up the cycle of menstrual contractions and pain.
Hope I helped!
Not being funny or perverted. But sex does reduce mensteral pains and such. A long hot bath helps.