'uterus cramping' after intercourse may be due to several disease states: uterine fibroids (benign uterus muscle tumors) can cause painful sex (dyspareunia) or cramping.
Also endometriosis may cause chronic or intermittent pelvic pain.
Any inflammation of pelvic structures (bladder/bowel) may cause pain/cramping, too. If symptoms persist:time to see primary doctor/gyn. Hope you are better soon!
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