Your question refers to the pain in your lower back that is worse before and during your period.

This type of description is common amongst women who have referral pain and tension in the lower back possibly due to a hormonal imbalance. It is thought that as your period approaches, ligaments become looser, and may contribute to instability in the sacro-iliac joints temporarily. If you have a pre-existing issue with your sacro-iliac joints, it may be exacerbated during certain parts of your menstrual cycle.

A remedy that may be useful is performing exercises that emphasize your glute muscles. The glutes provide stability to the sacro-iliac joints. You may wish to do a google search on "glute hip extension exercise" and select an exercise that is appropriate for your fitness level.

Sam Visnic NMT