The article provides a rare observation of a 34-year-old woman who, 12 years before admission to a urological clinic, a gynecologist installed an intrauterine contraceptive device (IUD). The subject migrated into the abdominal cavity, and after 10 years the patient developed dysuria and hematuria. In October 2017, ultrasound and cystoscopy revealed the migration of IUD into the bladder. A foreign body was removed from the bladder - an IUD of a T-shape with the formation of a stone on it with a maximum size of 4.5 cm. During a follow-up examination after 2 years, pathology was not established.

Keywords: foreign body, stone formation, perforation, bladder, intrauterine contraception, complications