Every month during my period and a week after i get lower back pain and stiffness, only at night time, it wakes me up the pain is that bad. thanks

Night pain, not good: I am always worried when pain wakens my patients. Although it may not be serious, and related to a common condition, before assuming it is due to your back, I would suggest you have your gynecologist evaluate you for conditions in the ovaries or surrounding organs that could cause this. Endometriosis should be looked for as well.