why do girls feel pain during menses?

Question: why do girls feel pain during menses?
- Keywords:
  menstruation
Asked by 673orange23 to Jacob, Eve on 25 May 2018.
- Evelyn Kabia answered on 25 May 2018:
  
  During the menstrual period, the uterus contracts to help expel its endometrial lining. Hormone like substances called prostaglandins are involved in pain and inflammation trigger the uterine muscle contractions. Higher level prostaglandins are associated with more-severe menstrual cramps.

Question: why do girls feel pain during menses?