Hello,
Genital tract in which the IUD is put is completely different from the urinary tract.So that has no relation to blood in urine. If you are passing different-shaped clots in your stream, they could represent bleeding from the urethra. Clots can be wormlike, and if associated with pain it could represent clots coming from your ureters(tubes from your kidneys to your bladder).
When the blood in the urine is at the beginning of urination, it most likely comes from the urethra, (the tube from the bladder to the outside). Blood throughout urination is most likely from the bladder or kidneys or ureters (the tubes connecting the kidneys and the bladder).
Diagnostic tests that may be performed include Urinalysis, Urine culture, X-rays of the kidneys, Cystoscopy, IVP, Abdominal ultrasound and CT scan of the abdomen.
The treatment will depend on the cause of the blood in the urine. I would sincerely advise you to consult a urologist for this.
I hope it helps.Take care and regards