Iud fell out

Question for the ladies with IUD this would be my second iud my first one after a year of having it got embedded in my uterus half way so they removed it and then while on the pill I got pregnant within like days of getting it removed. I had my son then I got it placed again after him well a year later my second iud literally fell out of me . Does anyone have this experience? Does my uterus just like try to get rid of it after a year or what ?