The intrauterine contraceptive device (IUD) is considered to be the most popular method of reversible contraception in developed countries because of its safety, efficacy and low cost.

One significant, but uncommon, complication is uterine perforation during or after insertion. A recent large, prospective cohort study reported an incidence of 1.1-1.4 per 1,000 insertions.¹ IUDs are not always inserted by healthcare professionals with the requisite skills and experience and follow-up after IUD insertion does not always take place.

As a result IUDs may be forgotten, lost or misplaced. In this report, we present a case in which an IUD migrated to the bladder.

CASE REPORT

A 30-year-old lady presented to the gynaecologist with persistent vaginal bleeding following insertion of an IUD.

At the time, abdominal examination was unremarkable and speculum examination revealed normal external genitalia and cervix.

A transvaginal ultrasound showed a normal uterus, normal ovaries and no adnexal masses or free fluid. It was assumed that the IUD had fallen out.

Around the same time she presented to her GP with a short history of dysuria, intermittent visible haematuria and recurrent urinary tract infections (UTIs).

After initial management in general practice for 12 months, she was referred to the urology department for further investigation.

She underwent flexible cystoscopy, which demonstrated the presence of an IUD within the bladder. Under general anaesthesia, we found that the body of the IUD had penetrated the bladder mucosa and become embedded in the right lateral wall of the bladder.

The IUD was markedly calcified but was easily removed endoscopically as a whole unit with grasping forceps.

A three-week postoperative cystogram ruled out the presence of a fistula. At the six-week postoperative review she was asymptomatic and well.

DISCUSSION

The Faculty of Sexual  and Reproductive Healthcare (FSRH) has recently updated its guidance on intrauterine contraception (see box 1).²

The exact mechanism that causes uterine perforation and migration of an IUD is not entirely understood. There are two main mechanisms of uterine perforation suggested.

The first occurs at the time of insertion. It is associated with severe abdominal pain and is closely related to the time and technique of insertion, the type of IUD, the skill of the clinician, and the anatomy of the cervix and uterus. The most significant factor implicated is operator experience.

The second proposed mechanism is by gradual pressure necrosis of the uterine wall by the IUD with migration out of the uterus.

Pregnancy may contribute to the erosion of the uterine wall by an IUD.

Alternatively, an IUD in the bladder can be the consequence of inserting it erroneously through the urethra.

Patients may be asymptomatic and the migrated device detected during investigations for other reasons.

Symptoms of a dislocated IUD are non-specific and include dysuria, suprapubic pain, irritative bladder symptoms and recurrent UTIs.

Every woman who has recurrent UTIs should undergo urinary tract imaging.

A migrated intravesical IUD could eventually become either partially encrusted or could instigate calculus formation.

However, secondary bladder stone formation is very uncommon. Karsmakers and colleagues reported a case of a significant calculus formation around a migrated IUD, which created a vesicovaginal fistula causing urinary incontinence and recurrent UTIs, contributing to terminal kidney failure.³

The presence of an intravesical calculus against the background of an IUD insertion should always raise the suspicion of a migrated device.

A secondary hysterosalpingography in order to define the relation between the uterus and the IUD is a diagnostic option but it restricts the option for its simultaneous removal.⁴ Cystoscopy offers the advantage of simultaneous confirmation of the diagnosis and retrieval of the foreign body.

The most effective management is still prevention. All migrated IUDs should be removed even if asymptomatic in order to prevent potential complications.

The most common reported procedure used to remove an intravesical IUD is cystoscopy. Suprapubic cystotomy and open surgery may be required in cases of large stones surrounding the IUD making it difficult to extract endoscopically.

A less common method is intracorporeal lithotripsy and IUD extraction.

CONCLUSION

Although it is very rare, this case highlights the possibility of late uterine perforation and migration of an IUD. Every symptomatic woman, even during pregnancy, with a history of IUD use should alert the clinician to the possibility of total or partial migration of the device.