Menstrual cramps or dysmenorrhea refers to severe lower abdominal pain during periods. Menstrual cramps are caused by the uterus contracting forcefully to expel the uterine lining. This leads to abdominal cramps. The blood and tissue eliminated from the vagina throughout the menstrual cycle is the uterine lining.Usually, the pain starts a day or two before the actual start of the menstruation. The common symptoms of dysmenorrhea are abdominal discomfort due to throbbing pain, aches in the inner thighs, lower back, and hips, and additional signs including headaches, nausea, dizziness, tiredness, and diarrhea.