yes i had an ultrasound because the doctors claimed they could not find it. it was lost somewhere in some tissue far away from my uterus. my doctors trashed my ultrasound pictures so i don't know where it was all i know is they wanted to put me to sleep and use a camera to find it a month later.
i wanted it out asap so i went to a better doctor because the first doctor caused an infection and refused to give me any medicine.
if you have pain then there could be a problem or your body just trying to expell the thing.
i don't know why doctors play dumb when you want it removed. if you are in pain with and iud or they can't find the strings then it is an emergency, but most doctors just send women home. i would not go home in pain with a lost merina and bleeding until i had an ultrasound.
the longer its in the more problems it causes and the higher the doctor or hospital bill.