Retained fetal bones following termination of pregnancy mistaken for an intrauterine contraceptive device.

©FSRH J Fam Plann Reprod Health Care 2009: 35(3) Case report A 33-year-old woman of non-UK origin who travelled frequently in her job presented complaining of chronic pelvic pain over the previous 4 years with intermittent exacerbations. The pain was situated mainly in the suprapubic region, was unrelated to her periods or to sexual intercourse and had not been relieved by routine analgesics. She had had two surgical terminations of pregnancy (TOPs), at 14 and 21 weeks’ gestation, 10 years and 8 years previously. She did not disclose the background to these late terminations. She used a combined oral contraceptive pill for contraception for the past 4 years. Following an acute exacerbation of pain in her home country, the patient had been investigated with an ultrasound scan, which had suggested the presence of an intrauterine device (IUD). At the family planning clinic a nurse practitioner was unable to see the threads of the supposed IUD and the patient was therefore referred to the clinic dealing with difficult problems in the Department for Sexual and Reproductive Health. She presented a copy of the ultrasound scan image from her home country, but no written report. Although the single image of one plane of this transvaginal scan showed a structure with the appearance expected with an IUD, the history and the absence of a thread suggested further investigation. Abdominal examination revealed no masses or tenderness. The vulva and vagina looked normal and no IUD thread was seen at the cervical os. Bimanual examination was entirely normal. Given the evidence of the original scan image, the gestation at the second TOP, the patient’s certainty that no intrauterine contraceptive device had then been inserted and the continuing pelvic pain, a further ultrasound scan was performed to clarify the diagnosis. This demonstrated highly echogenic linear structure, although not as straight or regular as would be expected with an IUD (Figure 1). The differential diagnosis was retained fetal bones or an unusual IUD. The first diagnosis was considered more likely because of the kinked linear appearance with irregularly increased thickness. It was explained to the patient that given her history and the available evidence, the echogenic appearance might have arisen from retained fetal bones following the second TOP. She agreed to investigation and consented to an Retained fetal bones following termination of pregnancy mistaken for an intrauterine contraceptive device