Sexual intercourse is not a recognized cause of IUD displacement or expulsion in the medical literature. The forces involved in penetrative sex do not reach or act on the IUD itself, which sits inside the uterine cavity, well past the cervix. That said, the fear is common and understandable, and the broader topic of what actually does move an IUD out of place is worth exploring in detail.
Why Sex Does Not Dislodge an IUD
An IUD sits inside the uterus, a pear-shaped organ separated from the vaginal canal by the cervix. During penetrative sex, a penis or toy enters the vaginal canal but does not pass through the cervical opening, which is only a few millimeters wide. The IUD’s T-shaped arms hold it against the walls of the uterine cavity, and nothing that happens during intercourse exerts direct mechanical force on the device. A partner might occasionally feel the IUD strings, which hang through the cervix into the upper vagina, but bumping against strings is not the same as pushing on the device itself.
No peer-reviewed study has identified sexual intercourse as a risk factor for IUD expulsion. The established risk factors include the timing of insertion relative to childbirth, the shape of the uterus, and uterine contractions during menstruation. Orgasm does cause uterine contractions, but these are brief and mild compared to the sustained contractions of menstruation or postpartum recovery, and they have not been linked to displacement in clinical data.
What Actually Causes IUD Expulsion
The biggest risk window for expulsion is the first few months after insertion, while the uterus adjusts to the device. Uterine contractions during this period and during menstrual periods can push the IUD downward, sometimes partially and sometimes completely out of the uterus.1ScienceDirect. Intrauterine Device Expulsion After that initial adjustment period, the risk drops considerably.
Timing relative to childbirth matters a lot. When IUDs are placed during or shortly after delivery, expulsion rates are much higher than when they are placed at a routine office visit weeks or months later. A systematic review of postpartum IUD placement found that IUDs placed immediately after delivery had a complete expulsion rate of about 10%, while those placed at a standard interval visit had a rate closer to 2%.2PubMed Central. Expulsion of intrauterine devices after postpartum placement by timing of placement, delivery type, and intrauterine device type: a systematic review and meta-analysis Vaginal delivery was associated with higher expulsion rates than cesarean delivery, likely because the uterus undergoes more vigorous contractions and involution after a vaginal birth.
Overall expulsion rates across the broader IUD-using population range widely depending on the study and the follow-up period. One large study found a cumulative expulsion rate of roughly 10 per 100 users at three years.3PubMed Central. Association of Age and Parity With Intrauterine Device Expulsion A larger dataset from a European study pegged one-year cumulative expulsion at about 2.3% for both hormonal and copper IUDs.4PubMed. Association between intrauterine device type and risk of perforation and device expulsion: results from the Association of Perforation and Expulsion of Intrauterine Device study The range reflects differences in study populations, insertion timing, and how carefully researchers tracked partial versus complete expulsions. But across all of this data, sexual activity does not appear as a contributing factor.
Anatomical Factors That Increase Risk
The shape and position of your uterus play a role. A study of over 500 women with IUDs found that those with a retroverted (backward-tilting) uterus were more likely to have a malpositioned device compared to those with an anterior (forward-facing) uterus. Women with structural uterine differences, including fibroids or a septate uterus, also had higher rates of malposition.5Contraception. Uterine structural abnormality and intrauterine device malposition: analysis of ultrasonographic and demographic variables of 517 patients These are things that exist before the IUD goes in and have nothing to do with what happens during sex afterward.
A shorter uterine cavity can also be a factor. One study found that women who experienced heavy menstrual bleeding after copper IUD insertion tended to have shorter uterine measurements, and that women who reported pelvic cramping at three months showed measurable downward movement of their device on ultrasound.6PubMed. Relationship between copper IUD complications and ultrasonographic findings A uterus that is too small for the device creates a poor fit, which makes displacement more likely regardless of activity.
Does IUD Type Matter
The two main categories of IUDs are hormonal (levonorgestrel-releasing) and copper. You might assume one type stays put better than the other, and the evidence is somewhat mixed but leans in one direction. The large European study mentioned earlier found that copper IUDs had a slightly higher adjusted risk of expulsion compared to hormonal IUDs.4PubMed. Association between intrauterine device type and risk of perforation and device expulsion: results from the Association of Perforation and Expulsion of Intrauterine Device study A retrospective cohort study found an even more pronounced difference, with about 10% of copper IUD users experiencing expulsion over the study period compared to about 5% of hormonal IUD users.7PubMed Central. Continuation of copper and levonorgestrel intrauterine devices: a retrospective cohort study
However, one other study found no meaningful difference between the two types, with nearly identical three-year expulsion rates.3PubMed Central. Association of Age and Parity With Intrauterine Device Expulsion The discrepancy likely comes from differences in how these studies were designed and who was enrolled. Hormonal IUDs tend to thin the uterine lining and reduce menstrual flow, which may reduce the strength of uterine contractions that push the device downward. But either way, the type of IUD you have does not change whether sex is a risk factor. It is not.
How to Tell If Your IUD Has Moved
Displacement can happen silently, but it often announces itself. The most common signs are new or worsening pelvic pain, changes in bleeding patterns, and pain during intercourse. That last symptom is worth highlighting because it creates a chicken-and-egg confusion: people sometimes assume sex caused the problem when the IUD had already shifted for other reasons and sex simply revealed it through discomfort.
In the study of uterine anatomy and IUD malposition, vaginal bleeding and pain were strongly associated with a displaced device. Missing IUD strings at a clinical exam also raised the odds that the IUD was out of position.5Contraception. Uterine structural abnormality and intrauterine device malposition: analysis of ultrasonographic and demographic variables of 517 patients If your partner suddenly starts feeling something hard or poky during intercourse that was not there before, that could indicate the IUD has shifted downward toward the cervix.
Ultrasound is the gold standard for checking IUD position. A standard pelvic exam where the provider feels for the strings can miss problems. In one study, four women whose IUDs appeared correctly placed during a gynecological examination were found to have misplaced devices on transvaginal ultrasound.8PubMed. The use of transvaginal ultrasonography compared to routine gynecological examination to check the location of an intrauterine contraceptive device Three-dimensional ultrasound is even more sensitive, particularly for detecting cases where the IUD’s arms have become embedded in the uterine wall.9PubMed Central. Ultrasonography of intrauterine devices
Checking Your Own Strings
You may have been told to periodically feel for your IUD strings with a finger to make sure the device is in place. This is standard advice on IUD package labels. But research suggests this guidance may be less useful than it sounds. In one study, fewer than half of IUD users were both willing and able to find their own strings.10PubMed Central. Women’s willingness and ability to feel the strings of their intrauterine device The researchers noted that insisting every user check their strings could lead to unnecessary anxiety and clinic visits when women simply cannot reach or identify them.
There is also a small irony: the same study flagged the possibility that aggressive string-checking might itself nudge the device. That does not mean you should avoid it entirely, but it does mean that frantic prodding after every sexual encounter is not helpful. If you can feel the strings and they seem the same length as usual, that is reassuring. If you cannot feel them, it does not automatically mean something is wrong. Strings sometimes curl up around the cervix and become hard to reach. When in doubt, schedule an ultrasound rather than trying to investigate with your fingers.
Perforation Is a Different and Rarer Problem
Displacement and perforation are separate issues. Perforation happens when the IUD pushes through the uterine wall, either partially or completely into the abdominal cavity. This is rare, occurring in roughly one in 1,000 insertions, and it almost always happens at the time of insertion or shortly afterward, not during daily life or sex.11PubMed Central. Intrauterine devices and risk of uterine perforation: current perspectives Some research has found a link between breastfeeding and perforation, though the causal connection is not clear.
A perforated IUD that has migrated into the abdominal cavity is usually removed surgically, typically via laparoscopy. In rare cases, the device can work its way into the bowel or urinary tract. Pregnancy has also been reported with misplaced IUDs; one study found that about 15% of women with perforated IUDs were pregnant at the time of diagnosis.12Human Reproduction. Uterine perforation caused by intrauterine devices: clinical course and treatment Again, none of this is caused by intercourse. The mechanical event that leads to perforation involves the insertion instrument or gradual erosion through the uterine wall in the weeks following placement.
Where the Fear Comes From
The worry that sex will dislodge an IUD is widespread, particularly among younger people considering the device for the first time. A qualitative study of adolescents in New York City found that fear of expulsion was a significant barrier to choosing an IUD. Participants specifically mentioned intercourse and showering as moments when they worried the device might fall out.13PubMed Central. Fear of intrauterine contraception among adolescents in New York City One participant put it bluntly: “I just have a feeling it will fall out or something and then something will happen, pregnancy or something.”
This fear makes sense when you think about it from the user’s perspective. You have a foreign object inside your body, you know it can come out (the word “expulsion” is right there in the consent forms), and sex involves physical forces near the area where it lives. The mental leap from “there is a thing in my uterus” to “vigorous activity could shake it loose” feels logical even though it is anatomically wrong. The cervix acts as a barrier, and the uterine cavity is a closed space that does not get jostled by vaginal penetration.
Menstrual Cups and IUDs
While sex is not a risk, menstrual cup use has drawn more serious attention as a potential contributor to IUD displacement. The theoretical concern involves suction: when you remove a menstrual cup from the vagina, the vacuum seal it creates could tug on the IUD strings or apply downward pressure on the cervix. A systematic review noted this theoretical risk and found a handful of case reports linking cup removal to IUD expulsion, though the overall evidence was thin and no large study has confirmed a causal relationship.14PubMed Central. Menstrual cup and risk of IUD expulsion – a systematic review
If you use both a menstrual cup and an IUD, the practical advice is to break the suction seal before pulling the cup out. Pinch the base of the cup to release the vacuum rather than yanking it straight down. This reduces whatever small risk exists. Tampons and discs do not create the same suction concern, though any menstrual product that involves pulling something out of the vagina introduces a slim chance of catching a string.
When Pain During Sex Actually Signals a Problem
If sex starts hurting in a way it did not before your IUD was placed, that is worth investigating, but not because the sex caused something. Pain during intercourse with an IUD can mean the device has shifted, that one of its arms is embedded in the uterine wall, or that the strings are irritating your partner or catching on something. An IUD that has partially expelled can sometimes be felt at the cervix during deep penetration, which can hurt for both partners.
A partially expelled IUD needs to be removed and, if you want to continue with this form of contraception, replaced with a new one. There is no fix for a device that has moved partway out. If you and your provider confirm that the IUD is properly positioned and sex is still uncomfortable, the problem may be unrelated to the device itself. Conditions like cervicitis, endometriosis, or even normal cervical sensitivity can cause pain during deep penetration.
What Happens If Your IUD Does Come Out
A fully expelled IUD means you are no longer protected against pregnancy. If the device comes out and you have had unprotected sex recently, emergency contraception may be worth discussing with a provider. Many people do not realize their IUD has expelled, especially if it happens during a heavy period and exits with menstrual flow.
Most providers will offer to place a new IUD if you want one. Having one IUD expelled does increase the chance of it happening again, but it does not mean a second IUD is a bad idea. The decision depends on why the first one came out. If the expulsion was related to postpartum timing, for example, a placement at a later date when the uterus has returned to its normal size may solve the problem. If the issue is an unusually small or irregularly shaped uterine cavity, your provider might suggest a smaller IUD or an alternative method.
One retrospective study found continuation rates as high as 80% at one year for standard IUD users, meaning most people who get an IUD keep it in place and keep using it.15PubMed Central. Expulsion and continuation rates after postabortion insertion of framed IUDs versus frameless IUDs – review of the literature The odds are strongly in your favor that the device will stay put, and your sex life is not the variable to worry about.