An intrauterine device (IUD) is a small, T-shaped form of long-acting, reversible birth control placed inside the uterus to prevent pregnancy. A common concern is whether the device can shift or be knocked out of its correct position. While IUDs are highly secure, displacement is a rare but real possibility. This typically occurs when the body naturally attempts to expel the device. Understanding the circumstances and signs of movement is important for ensuring the device’s continued effectiveness.
Internal Factors Causing Displacement
The majority of IUD movement, or expulsion, is linked to the body’s natural processes rather than external force. The highest risk of displacement occurs within the first three months after insertion, as the uterus adjusts to the device. A primary cause is the force generated by strong uterine contractions, particularly during menstruation. These contractions can sometimes push the IUD partially or completely out of the uterine cavity.
The fit of the device within the uterine cavity is another significant internal factor. If the IUD’s size is not well-matched to the uterus, or if structural irregularities like fibroids are present, the risk of expulsion increases. Improper placement during the initial insertion can also lead to malpositioning later. The IUD should rest high in the upper part of the uterus; if it is situated too low, it is more susceptible to moving toward the cervix.
External Activities and IUD Stability
Many people worry that common physical activities or sexual intercourse could accidentally dislodge the IUD, but this is highly unlikely. The IUD is secured high inside the uterine cavity, well above the vagina and cervix. During penetrative sexual intercourse, a penis or sex toy will not reach the device itself. The gentle strings hanging from the cervix do not provide enough leverage to pull the IUD out of place. While a partner may occasionally feel the trimmed strings, this sensation does not indicate movement.
Intense physical activity, such as heavy weightlifting, running, or rigorous core exercises, is not a cause of IUD displacement. The forces generated by the external body are not sufficient to overcome the secure placement of the device within the uterus. Following insertion, healthcare providers may recommend resting briefly to minimize cramping and spotting. However, there is no evidence that resuming a full exercise routine causes the IUD to shift. Minor trauma, such as a bump or fall, also poses a negligible risk to a properly situated IUD.
Recognizing Signs of Migration
Recognizing that an IUD has moved often depends on noticing changes in physical symptoms or the IUD’s strings. A potential sign of displacement is the onset of unusual or severe cramping. This is especially true if the pain is sharp, persistent, and different from typical menstrual discomfort. Changes in bleeding patterns can also be a signal, such as experiencing heavier bleeding or increased spotting outside of the regular cycle.
The most practical way to monitor the IUD’s position is by checking the strings, a short length of thread that hangs through the cervix into the upper vagina. If the strings feel suddenly longer or shorter, or if they cannot be felt at all, the IUD may have shifted. If the strings are missing, they may have coiled up inside the cervix, or the device may have partially or fully expelled. Crucially, a person or their partner should never be able to feel the hard, plastic tip of the IUD itself. Feeling this plastic indicates that the device has moved significantly down toward the cervix.
Immediate Steps Following Suspected Movement
If any signs of IUD migration are present, the immediate step is to contact a healthcare provider for an evaluation. It is important to begin using a backup method of contraception immediately, such as condoms. A displaced IUD may not be effective at preventing pregnancy. The individual should avoid attempting to adjust, push, or remove the IUD themselves, as this could lead to further complications, including uterine perforation.
The healthcare provider will typically perform a pelvic examination and often an ultrasound to confirm the IUD’s exact location within the uterus. If the IUD is confirmed to be partially expelled or malpositioned, it will need to be removed. A displaced IUD carries an increased risk of unintended pregnancy and can lead to complications such as perforation of the uterine wall. The provider will then discuss options for inserting a new device or choosing an alternative contraceptive method.