Background: Osseous metaplasia of the endometrium is a rare disorder and can be associated with infertility. Although successful diagnosis and treatment have been widely reported, correct diagnosis in many cases still represents a challenge.
Case: A 40-year-old woman complaining of infertility presented with a diagnosis of retained intrauterine device (IUD) on ultrasound. Hysteroscopy revealed a normal endometrial cavity, but no IUD was visualized. Curettage pathology specimens showed chronic endometritis and calcification. Repeat hysteroscopy was performed because of persistent echogenic foci in the endometrium on follow-up ultrasound. Several irregular and calcified plaques were successfully removed.
Conclusion: Osseous metaplasia can be misdiagnosed because of its rare incidence. Physicians should be aware of osseous metaplasia in the differential diagnosis of patients with uncertain history who present with a sonographic image resembling an IUD.