Most women feel pain or discomfort before, as well as during the period, which is mostly caused by the contraction of the uterus to release the uterine pledget. The pain that slightly reminds of cramps is very common occurrence just before the period and usually lasts one or two days. It can feel in the pelvis, back, thighs or abdomen. Usually begins immediately under the navel and spreads to the thighs and backs. The intensity of these menstrual cramps differs from woman to woman.