Why do I get low back and leg pain during my period?

Low back and leg pain that predictably flares with your period can happen when pelvic inflammation irritates pain pathways that “refer” into the back, hips, buttocks, and down the leg. In some patients, endometriosis can be part of that story—either indirectly (pelvic inflammation and scarring increasing pressure and sensitivity around nearby nerves) or more directly if disease is affecting areas close to major nerves.

When period-related leg pain resembles sciatica—deep buttock pain, tingling, burning, or pain radiating down the back of the thigh—it raises the possibility of endometriosis-related sciatic irritation or pelvic floor involvement (often described as piriformis-type pressure on the nerve). These symptoms may start before bleeding, peak during the period, and linger afterward, and in more significant cases can be associated with weakness or changes in walking.

Because back and leg pain can also come from the spine, hips, or muscles, the key is the pattern and the full symptom “constellation,” including pelvic pain, bowel/bladder symptoms, or pain with sex. Our team can help you sort out whether your pain fits an endometriosis/adenomyosis pattern and, if needed, plan next-step evaluation such as targeted imaging and a strategy focused on lasting relief rather than temporary suppression.