The main way to check if your IUD is in place is by feeling for the strings. IUDs have thin threads that hang down through your cervix into the upper part of your vagina, and if you can feel them at a consistent length each time you check, your IUD is sitting where it should be. Fewer than 5% of IUDs are fully expelled within the first year, so displacement is uncommon, but knowing how to check gives you peace of mind between appointments.
How to Check Your IUD Strings
IUD strings feel like short pieces of fishing line. They’re trimmed by your provider after insertion so that just enough length extends through the cervix for you to reach with a fingertip. Over time, the strings tend to soften and curl around the cervix, making them less noticeable.
To check, wash your hands and insert one or two fingers into your vagina until you reach the cervix. The cervix feels firm and rounded, somewhat like the tip of your nose. You should be able to feel the thin strings coming out of the small opening. Don’t tug on them. You’re simply confirming they’re there and that they feel about the same length as the last time you checked.
If you’ve just had your IUD placed, wait a few days before your first check. Cramping after insertion is normal, and giving yourself time to recover makes the process more comfortable. After that, IUD manufacturers recommend checking once a month. A simple way to remember is to pick a consistent day, like the first of each month or the last day of your period. The CDC notes that routine follow-up isn’t strictly necessary, so if checking causes you anxiety rather than reassurance, it’s fine to skip it. But many people find it helpful, especially if they don’t get regular periods and want confirmation things are still in place.
What Normal Strings Feel Like
When everything is positioned correctly, you’ll feel one or two thin threads at a consistent length each time. You should not be able to feel any hard plastic poking through your cervix. The strings themselves are the only part of the IUD that extends beyond the uterus.
In rare cases, a partner may feel the strings during sex. This doesn’t mean the IUD has moved. If the strings are bothersome, your provider can trim them shorter. Long strings aren’t dangerous on their own, and you typically won’t notice them unless they extend far enough to be felt at the vaginal opening.
Signs Your IUD May Have Shifted
The most telling sign is a change in the strings. If they suddenly feel noticeably longer or shorter than usual, or if you can’t find them at all, the IUD may have moved. Another red flag is being able to feel the hard plastic base of the device at your cervix, which could mean it’s partially expelled.
Physical symptoms can also signal displacement. These include:
- New or worsening cramping that differs from your usual pattern
- Changes in menstrual bleeding, such as heavier periods or unexpected spotting
- Pain during sex that wasn’t there before
None of these symptoms on their own guarantee the IUD has moved, since they can overlap with normal cycle fluctuations. But if you notice one or more of them alongside a string change, that’s a stronger signal.
What to Do If You Can’t Feel the Strings
Missing strings don’t always mean the IUD has fallen out. Sometimes the strings curl up around the cervix or tuck into the cervical canal, making them hard to reach. Your uterine position can also shift slightly depending on where you are in your cycle, changing how easy the strings are to find.
If you can’t feel the strings after a couple of attempts in different positions, use a backup method of birth control (like condoms) until you can get checked. Your provider will typically start with a visual exam using a speculum to look for the strings. If they’re not visible, an ultrasound can confirm whether the IUD is still sitting correctly inside the uterus. Once correct placement is confirmed on imaging, you can rely on the IUD for contraception again even if the strings remain hard to feel on your own.
An IUD that has slipped down into the cervix is considered partially expelled and will need to be removed. A new one can be placed at the same visit if you’d like to continue with this method.
Perforation and Embedding
In rare cases, an IUD can push through the uterine wall (perforation) or become embedded in the muscle of the uterus. A study of 75 perforation cases found that about 71% of patients had symptoms: abnormal bleeding, abdominal pain, or both, typically combined with missing strings. The remaining 29% had no symptoms at all and were only diagnosed because the strings couldn’t be found during a routine visit or because of an unexpected pregnancy.
Perforation is uncommon enough that it shouldn’t cause everyday worry, but it’s worth knowing the pattern. Persistent pain that doesn’t improve in the weeks after insertion, bleeding that seems out of proportion to your normal cycle, and disappearing strings together warrant a prompt visit rather than a wait-and-see approach.
When the IUD Falls Out Completely
Complete expulsion means the IUD comes out of the uterus entirely. You might find it in your underwear, in the toilet, or notice it while removing a menstrual cup or disc. Sometimes you won’t see the device at all, but you’ll notice the strings are gone and your symptoms (heavier bleeding, cramping) suddenly change.
Expulsion is most likely in the first few months after placement. In clinical data, complete expulsion rates at 12 months were around 3% for IUDs placed in the early postpartum period and close to 0% for those placed at the standard six-to-eight-week interval. If your IUD does come out, you are no longer protected against pregnancy from the moment it leaves the uterus.
How Providers Confirm Placement
At routine visits, your provider may do a quick check for the strings using a speculum. This takes seconds and confirms the IUD hasn’t moved. If there’s any question about positioning, a transvaginal ultrasound provides a clear picture of exactly where the device is sitting. This is the definitive method for confirming correct placement and is painless, involving only an external or internal ultrasound probe.
You don’t need regular ultrasounds if your string checks are consistent and you have no symptoms. But if you’ve ever had trouble finding your strings, or you’ve experienced an expulsion in the past, asking for an ultrasound at your next visit can give you a reliable baseline.