Retained intrauterine fetal bone as a rare cause of secondary infertility.

Retention of intrauterine fetal bone is a rare cause of secondary infertility that should be considered when ultrasound demonstrates strongly shadowing echodensities in the endometrial space. It seems that the bone acts as an intrauterine contraceptive device as long as it is present in the cavity. Hysteroscopy is both diagnostic and therapeutic, with a generally good prognosis for future fertility in the absence of coexisting factors.