An intrauterine device (IUD) is a small, T-shaped contraceptive placed inside the uterus to prevent pregnancy. While IUDs are safe and effective, a rare complication is embedding, which occurs when the device becomes partially or completely stuck within the muscular wall of the uterus (myometrium). Embedding is distinct from a fully perforated device, which has passed entirely through the uterine wall. Both conditions are misplacements that require medical attention. Understanding the difference between normal sensations and signs of embedding is important for IUD users.
How a Properly Placed IUD Should Feel
A correctly positioned IUD should be unobtrusive; a person should not feel the device during everyday life. Following insertion, cramping similar to menstrual pain is common, typically strongest immediately after the procedure and subsiding within a few hours or days. Mild, intermittent cramping may persist for up to a week as the uterus adjusts. After this adjustment period, a properly seated IUD generally causes no ongoing physical sensation.
Changes in the menstrual cycle vary depending on the type of IUD used. Hormonal IUDs often lead to lighter periods and reduced cramping, while the non-hormonal copper IUD may cause heavier bleeding and more intense cramps. The only physical component a person should be able to feel is the soft, plastic threads extending into the upper vagina. Checking these strings regularly confirms the device is still in place, and neither the strings nor the IUD should be felt by a partner during sex.
Specific Sensations Indicating Embedding
The most notable sign of an embedded IUD is the onset of new or worsening pain beyond normal menstrual discomfort. This pain is often described as persistent, deep cramping or a sharp, localized sensation in the pelvis or lower abdomen. Unlike typical menstrual cramps, this discomfort may not respond well to over-the-counter pain medication and does not resolve after the initial adjustment period. This chronic, centralized pain is caused by the continued pressure of the device on the uterine wall.
A significant indicator of embedding is a change in the IUD strings, or their complete disappearance. During a self-check, the strings may feel significantly shorter than usual or be entirely absent. This occurs because the IUD has shifted, pulling the strings higher into the cervical canal or uterus as it settles into the uterine muscle. Discomfort during sexual activity (dyspareunia) can also arise if the IUD has moved and is pressing against the uterine tissue.
Abnormal bleeding patterns, such as heavy bleeding or bleeding between periods, can accompany embedding. Partial embedding causes inflammation and irritation of the uterine lining, leading to irregular or increased bleeding episodes. Severe abdominal tenderness or pain accompanied by fever or unusual discharge may also suggest embedding or a related complication, such as infection.
How Doctors Confirm IUD Position
When symptoms suggest an IUD is embedded or displaced, a healthcare provider begins the diagnostic process with a physical and pelvic examination. They attempt to visualize the cervix and locate the IUD strings, sometimes using a small brush if the strings are not immediately visible. If the strings are missing or the examination is inconclusive, imaging is the next step to confirm the device’s location.
Transvaginal ultrasound is the primary method used to assess the IUD’s position within the uterus. This procedure allows the provider to visualize the device and determine its distance from the top of the uterine cavity (fundus). An ultrasound confirms if the IUD is properly seated, has migrated downward, or if one of its arms has penetrated the myometrium, which confirms embedding.
If the ultrasound cannot locate the IUD within the uterus, the concern is that the device may have fully perforated the wall and migrated into the abdominal cavity. In this scenario, an abdominal X-ray or a Computed Tomography (CT) scan may be used to locate the device outside the uterus. These imaging techniques help determine the exact location of the IUD so a safe removal plan can be formulated.
Treatment and Removal of an Embedded Device
Once imaging confirms an IUD is embedded, removal is generally recommended, especially for patients experiencing pain or abnormal bleeding. The removal method depends on how deeply the device is lodged in the uterine wall. If the IUD is partially embedded and its strings are visible, a doctor may attempt removal in the office using gentle traction. If the device does not move easily or the strings are absent, further intervention is necessary to prevent trauma to the uterus.
For deeper embedding or missing strings, the device is typically removed using hysteroscopy, a minimally invasive procedure. This involves inserting a thin, lighted scope and small instruments through the cervix to visually locate the IUD and carefully free it from the uterine tissue. Hysteroscopy can often be performed on an outpatient basis. If the IUD has fully perforated the uterine wall and migrated into the abdominal cavity, laparoscopy may be required. Laparoscopy uses small incisions and a camera to retrieve the device from the abdomen.