Intrauterine Device Migrates to Bladder, Encrusted in Mineral Stones

A 39-year-old patient experienced persistent urinary urgency and dysuria, symptoms typically managed as recurrent cystitis with antibiotics. However, the symptoms continued to resurface. A CT scan ultimately revealed the underlying cause: one arm of her intrauterine device (IUD) had completely penetrated the uterine wall and lodged within her bladder. Mineral deposits in her urine had progressively formed stones around the displaced device. This case, documented by clinicians at Chengdu Second People’s Hospital and Sichuan University West China School of Medicine, is published in Frontiers in Medicine as an accepted manuscript, meaning the final formatted version is pending and subject to revision.

The Formation of Bladder Stones Around Foreign Objects

Bladder stones are rare in otherwise healthy adult women. When they do occur, a nidus—a foreign body within the bladder—is usually the catalyst.

Urine is a supersaturated solution that readily crystallizes upon encountering a surface. A plastic and copper device with an exposed arm provides an ideal substrate, allowing mineral crusting to accumulate gradually, layer by layer. Urologists observe this same process with retained stents and sutures.

This gradual timeline often delays diagnosis, as symptoms are urinary rather than gynecologic and manifest years after the initial insertion. Published literature documents devices discovered five years post-placement, stones forming nine years after insertion, and even a device placed 50 years prior that eroded into the bladder of an older patient. In another instance, a 31-year-old was treated repeatedly for chronic cystitis until imaging revealed the device embedded in her bladder wall.

Assessing the Actual Risk

While this case is alarming, the underlying statistical risk remains low.

According to National Center for Health Statistics survey data, long-acting reversible contraceptives—including IUDs and implants—were the current contraceptive method for 10.5 percent of American females aged 15 to 49, with IUDs alone accounting for 8.1 percent. Usage was highest among women in their twenties.

In the context of this prevalence, perforation rates are reassuring. The European Active Surveillance Study on Intrauterine Devices tracked over 61,000 women, and its five-year extension reported perforation rates of 2.1 per 1,000 insertions for hormonal devices and 1.6 per 1,000 for copper devices. No perforation in this cohort resulted in serious injury to abdominal or pelvic structures. A larger American cohort of 326,658 individuals found a one-year cumulative perforation risk of 0.21 percent, aligning with these figures.

Complete migration into the bladder is even rarer, representing a small subset of an already uncommon event. A systematic review identified only about 40 such cases reported worldwide over a decade.

Two risk factors stand out from the European surveillance data: breastfeeding at the time of insertion and placement in the months immediately following delivery were both associated with a several-fold increase in perforation risk. Furthermore, roughly one-third of perforations were detected more than 12 months post-insertion, underscoring the importance of follow-up.

A Multi-Stage Surgical Intervention

Extracting the device required a sequence of three distinct procedures.

The surgical team performed transurethral bladder lithotripsy to fragment and remove the stones, followed by laparoscopic repair of the bladder wall and hysteroscopic retrieval of the IUD. The device was extracted intact, the stones were completely cleared, and the patient recovered without complications.

This complex approach highlights a clinical challenge: when a device has been embedded long enough for mineral crusting to occur, fibrotic tissue often anchors it to the bladder wall, making transurethral extraction insufficient. In a similar case involving a 31-year-old patient, transurethral removal failed due to fibrosis, necessitating a laparoscopic approach.

The authors offer a straightforward recommendation: follow-up examinations after IUD insertion are essential, with ultrasound serving as the preferred method to confirm device position. Furthermore, recurrent urinary symptoms in a woman with an IUD should prompt clinicians to suspect migration rather than reflexively treating a presumed infection, with CT imaging used to confirm the diagnosis.

Clinical Context and Limitations

This case is not an argument against intrauterine devices, nor does the report intend it as such. IUDs remain among the most effective reversible contraceptives available, and extensive surveillance studies exist precisely because their widespread use means even rare events become statistically measurable.

It is important to classify the evidence accurately. This is a retrospective single-patient case report, which cannot establish incidence rates or identify specific at-risk populations. The perforation rates cited are derived from large prospective and population-based studies, which provide a more reliable assessment of actual risk. One caveat specific to this report: because it is currently an accepted manuscript rather than a final published article, the details may be revised before the version of record is released.

Nevertheless, the case illustrates a recognizable clinical pattern: a device inserted years prior, symptoms indicative of a urinary issue rather than a gynecologic one, and a diagnosis achieved only after the appropriate imaging is ordered. Any IUD user who cannot feel the strings, or who experiences persistent urinary symptoms despite treatment, should raise this possibility with their clinician.

Key Questions Answered

What happened in this case? One arm of a 39-year-old woman’s IUD migrated into her bladder, where stones formed around it. Physicians successfully removed both.

What were her symptoms? Recurrent urinary urgency and painful urination, a pattern easily mistaken for repeated urinary tract infections.

How common is IUD perforation? Large prospective studies report roughly 1.6 to 2.1 perforations per 1,000 insertions, with no serious organ injuries recorded in the largest European cohort.

Who is at higher risk? Breastfeeding at the time of insertion and placement soon after delivery were both associated with higher perforation risk in surveillance data.

Why did stones form around the device? Urine is rich in minerals, and any foreign surface sitting in the bladder can act as a nidus for crystal accumulation over months or years.

Is this report final? Not yet. It is an accepted manuscript, so the formatted version of record has not been published and the text may still be edited.

Source link