How to Tell If Your IUD Is Embedded: Warning Signs

An embedded IUD pushes into or through the muscular wall of the uterus, and the most common warning signs are abnormal bleeding, pelvic pain, and changes in your IUD strings. In a study of patients with confirmed perforation or embedding, roughly seven in ten reported some combination of those three symptoms, though the rest had no symptoms at all. That split makes embedding tricky: when it announces itself, it does so with recognizable signals, but it can also stay silent for months or years.

What “Embedded” Actually Means

An IUD is designed to sit inside your uterine cavity, held in place by the arms of the device pressing gently against the walls. Embedding happens when part of the device penetrates into the myometrium, the thick muscular layer of the uterus. The arm tips or the stem push into the muscle but do not break through the outer surface (the serosa) into the abdominal cavity. Clinically, embedment is defined as penetration of the myometrium by the arm or stem of the IUD without extension through the serosa.¹

Embedding sits on a spectrum with full perforation. In a partial perforation, the device may be partly in the cavity and partly in the muscle, or partly in the muscle and partly poking into the abdominal space. In a complete perforation, the entire device has migrated out of the uterus and sits free in the pelvis or abdomen.² The distinction matters because embedding is more common and harder to diagnose than a full perforation, and the symptoms can be subtler. A large cohort study defined partial perforation as an IUD embedded in the myometrium as seen on imaging or at the time of removal, while complete perforation meant the device was found in the pelvis or abdominal cavity.³

How does the IUD end up there? The process is usually gradual. If the device is slightly too large for your uterine cavity, or if the pointed tips press against the wall at an angle, the device slowly pushes into the muscle over weeks or months. Uterine contractions may help drive it deeper. This slow penetration causes tissue damage along the way, which is why pain and bleeding often build up before embedding is caught.⁴

The Warning Signs You Can Feel

The most reliable data on symptoms comes from a study of 75 women with confirmed IUD perforation. About 71% had some combination of abnormal bleeding, abdominal or pelvic pain, and missing IUD strings.⁵ Those three symptoms form the classic triad to watch for, though you may only have one or two of them.

Pelvic pain: This can range from a dull, persistent ache in the lower abdomen to sharp, sudden pain on one side. One case report described a woman who developed sudden right-sided pelvic pain with no other symptoms at all. Imaging revealed her IUD had shifted into the cervical canal, and the pain resolved completely once the device was removed.⁶ Pain during sex (especially deep penetration) or cramping that worsens over time rather than improving after the initial insertion period are also red flags.
Abnormal bleeding: Heavier periods, spotting between periods, or irregular bleeding that starts weeks or months after insertion can signal that the device has shifted. Some bleeding changes are normal in the first few months after getting an IUD, so what you are looking for is a change from your established post-insertion pattern.
String changes: Your IUD strings should hang through the cervix by about two to three centimeters. If they feel shorter, longer, or have disappeared entirely, that suggests the device has moved. A shortening of the strings may mean the IUD has shifted upward and pulled the strings with it; lengthening may mean it has descended toward the cervix. Complete disappearance can mean the device has embedded deeply enough that the strings have retracted into the uterine cavity or curled around the device.¹

Pain and bleeding together, especially when accompanied by string changes, are the strongest signal. But none of these symptoms on their own proves embedding. They overlap with other conditions, from normal IUD side effects to infections. The point is not to diagnose yourself but to recognize when something has changed enough to warrant a visit to your provider.

When There Are No Symptoms At All

Here is where things get uncomfortable: a large proportion of embedded IUDs cause no noticeable symptoms. A study of 130 patients with IUDs that could not be removed in the usual way found that 128 of them had embedded devices. Half of those patients had no complaints whatsoever; the other half reported pain or menstrual problems.⁷ This means you cannot rely on symptoms alone to rule out embedding.

The practical takeaway is that routine follow-up matters. Clinical guidelines recommend a pelvic exam within about six weeks of insertion to confirm the strings are visible and the device is in the right position.¹ If your provider does not schedule this automatically, ask for it. Beyond that initial check, monthly self-checks of your strings (clean hands, reach for the cervix, feel for the threads) are your best ongoing surveillance tool. If you can feel the strings and they seem the same length they have always been, things are likely fine. If anything feels different, get it checked.

Who Is at Higher Risk

Embedding and perforation are uncommon overall. Across a large study of more than 300,000 IUD users, the five-year rate of perforation was well under one percent for both hormonal and copper devices.⁸ But certain circumstances raise your risk meaningfully.

Postpartum Insertion and Breastfeeding

Having an IUD placed in the weeks after childbirth is the single most studied risk factor for perforation. A large multisite cohort study found that the hazard of perforation was highest when insertion happened between four days and six weeks postpartum, with a risk roughly six to seven times that of non-postpartum insertion.⁹ Breastfeeding adds an independent layer of risk on top of the postpartum timing. In that same study, breastfeeding at the time of insertion was linked to about a 37% higher hazard of perforation even after accounting for the postpartum period itself.⁹

An updated systematic review confirmed the pattern: breastfeeding at the time of IUD insertion was consistently associated with higher perforation risk across multiple studies, with relative risk estimates ranging from about 1.4 to over 10 depending on the study and timing.¹⁰ The likely explanation involves hormonal changes during lactation. Estrogen levels drop while breastfeeding, which can thin the uterine wall and make it easier for the device to push through. The postpartum uterus is also still involuting (shrinking back to its pre-pregnancy size), and the tissue is softer than usual.

This does not mean you should avoid getting an IUD while breastfeeding. The absolute risk remains low. But it does mean that if you had your IUD placed in the early postpartum period and were breastfeeding at the time, you should be especially attentive to the warning signs described above and keep up with follow-up appointments.

A Smaller Uterine Cavity

A mismatch between the size of the device and the size of your uterus plays a role. Research using three-dimensional ultrasound found that patients with embedded IUDs had a smaller fundal endometrial cavity diameter compared to patients with normally positioned devices.¹¹ A separate study found that women whose uterine width measured less than about 41.5 millimeters on ultrasound were more likely to have their IUD displaced.¹² In plainer terms, if your uterus is on the smaller side, a standard-sized IUD may press harder against the walls, increasing the chance that the arms slowly dig into the muscle. People who have never been pregnant tend to have smaller uterine cavities, which may partly explain why some providers recommend smaller-format IUDs for them.

How Embedding Is Diagnosed

Your provider cannot see an embedded IUD during a routine pelvic exam. If your strings are missing or your symptoms suggest the device has moved, imaging is the next step. A standard two-dimensional transvaginal ultrasound can often show whether the IUD is roughly in the right place or has shifted. But standard ultrasound has a real blind spot. In one study of 167 patients who had their IUDs evaluated using three-dimensional ultrasound with a reconstructed coronal view, about 17% had IUD arms abnormally located within the myometrium, and those abnormal positions were only visible on the 3D view, not on conventional imaging.¹³

This is an underappreciated point. If you are having symptoms and a regular ultrasound comes back “normal,” it may be worth asking about a 3D ultrasound, particularly if your provider has access to one. The 3D coronal view can show the relationship between the IUD arms and the uterine wall in a way that flat imaging simply cannot. In cases where the IUD appears to be completely outside the uterus or deep in the abdominal cavity, a CT scan or X-ray may be used instead. But for the far more common scenario of partial embedding, 3D ultrasound is the gold standard.

When symptoms are associated with imaging findings that confirm embedding, removal is recommended.¹ If the device is embedded but you have zero symptoms, the decision about whether to leave it or remove it is more nuanced and should be discussed with your provider.

What Removal Looks Like

Removing an embedded IUD is not the same as a routine removal where the provider simply pulls on the strings. If the strings are visible and the device is only mildly embedded, the provider may try a standard removal first, but extra resistance is a sign that something more is needed. Hysteroscopy, a procedure where a thin camera is passed through the cervix into the uterus, is the most common approach for embedded devices. It allows the provider to see exactly where the IUD is and extract it under direct visualization. In one case series, all patients who had their embedded or retained IUDs removed by hysteroscopy had unremarkable recovery courses and no readmissions.¹⁴

For cases where the IUD has partially or completely perforated through the uterine wall into the abdominal cavity, laparoscopy (a minimally invasive surgical approach through small abdominal incisions) or, rarely, open surgery may be necessary.² These are uncommon scenarios, but they underline why addressing embedding before it progresses matters.

After Removal and Getting a New IUD

If you want another IUD after having an embedded one removed, you typically can. In straightforward cases, a new device can be placed immediately. However, if the removal required cutting into the uterine muscle (endomyometrial resection), it may be advisable to wait two to three menstrual cycles to allow the tissue to heal before reinserting a new device.¹⁵ Your provider can advise on timing based on how much tissue was involved.

If the reason the IUD embedded was a size mismatch, your provider may recommend a smaller-format device the second time around, or an alternative contraceptive method altogether. If postpartum timing or breastfeeding was the likely driver, a later insertion date or additional monitoring may make a second attempt safer.

Does the Type of IUD Matter

Both hormonal (levonorgestrel-releasing) and copper IUDs can embed, but there is a modest difference in perforation rates between them. A large study of more than 320,000 women found that the five-year cumulative incidence of perforation was about 0.6% for hormonal IUDs and about 0.5% for copper devices. After adjusting for other factors, the hazard of perforation was roughly 50% higher with hormonal IUDs compared to copper.⁸ In absolute terms, both numbers are small, but the difference is consistent across studies. One proposed explanation is that the levonorgestrel released by hormonal IUDs thins the endometrium locally, potentially making it easier for the device to contact and penetrate the myometrium. The copper IUD, by contrast, triggers a localized inflammatory response that thickens the endometrium, which could create more of a buffer.

Expulsion rates, interestingly, run in the opposite direction. Copper IUDs are slightly more likely to be expelled (pushed out by the uterus) than hormonal ones.⁸ You can think of it as a continuum of mismatch responses: if the uterus rejects the device outward, that is expulsion; if the device pushes inward instead, that is embedding and eventually perforation. The direction it goes depends on the interplay between uterine contractions, device size, and the softness of the wall.

When to Seek Care Urgently

Most embedded IUDs are not emergencies. The embedding process is usually slow, and getting it evaluated within a few days of noticing symptoms is reasonable. But there are scenarios where you should not wait.

Sudden severe pain: Sharp, intense pelvic pain that comes on without warning could indicate that the IUD has perforated through the uterine wall. This is especially true if the pain is accompanied by dizziness, lightheadedness, or signs of internal bleeding.
Fever with pelvic pain: This combination raises concern about infection, which can develop if an embedded IUD creates a path for bacteria into the uterine muscle or abdominal cavity.
Positive pregnancy test: If you suspect embedding because your strings have changed and you also get a positive pregnancy test, contact your provider right away. An IUD that has shifted may no longer provide reliable contraception, and a pregnancy with a displaced IUD carries additional risks.
Inability to feel your strings combined with new symptoms: Missing strings alone are not always cause for alarm; the strings sometimes curl up around the cervix and become hard to reach. But missing strings plus new pain or bleeding is a stronger signal that the device has moved significantly.

The Slow-Burn Mechanism

Understanding how embedding happens can help you make sense of the timeline. Unlike perforation at the moment of insertion (which does happen, but accounts for a minority of cases), most embedding develops over weeks to months. The pointed tips of the IUD arms press against the uterine wall during normal contractions. If the cavity is smaller than the device, or if the uterus is softer than usual (as in the postpartum period), those tips slowly dig into the muscle. Tissue damage and inflammation accumulate, and the device migrates further inward with each contraction cycle. Pain and abnormal bleeding along this path serve as warning signs that the process is underway.⁴

This gradual progression explains why symptoms from embedding tend to appear weeks or months after insertion rather than immediately. It also means that catching embedding early, before the device pushes all the way through the wall, avoids the more complex surgical scenarios that complete perforation requires. If you notice new or worsening pain and bleeding at any point during the life of your IUD, even years after placement, do not dismiss it as normal. IUDs do not typically develop new side effects out of nowhere after a long uneventful period. A change in symptoms deserves investigation.

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