What are the next steps for a patient with a newly placed Intrauterine Device (IUD) where the strings cannot be visualized?

Management of Non-Visible IUD Strings After Placement

Obtain a transvaginal ultrasound immediately to confirm the IUD location within the uterine cavity. 1, 2

Initial Diagnostic Approach

When IUD strings cannot be visualized after placement, the device may still be properly positioned in the uterus, may have been expelled, or may have perforated the uterine wall. 1 The critical first step is imaging to determine location before making any management decisions.

Ultrasound Evaluation

• Perform transvaginal ultrasound as the first-line imaging modality to confirm whether the IUD remains in the uterine cavity and assess its position. 1, 2
• The IUD should appear centrally located within the endometrial cavity, with the crossbar (if present) positioned in the fundal portion. 3
• Three-dimensional ultrasonography can be particularly helpful when standard 2D imaging has difficulty visualizing the device, as it can better detect subtle malpositions including side-arm embedment. 4

If Ultrasound Shows No IUD in Uterus

• Obtain an abdominal X-ray to rule out uterine perforation if the IUD cannot be located on ultrasound. 2, 5
• Do not assume expulsion without radiographic confirmation, as perforation can present with minimal or atypical symptoms that may be missed for years. 5
• A plain abdominal radiograph is relatively inexpensive, non-invasive, and can definitively locate a radiopaque IUD anywhere in the abdomen or pelvis. 5, 3

Management Based on IUD Location

Properly Positioned IUD (Strings Not Visible)

• The IUD can remain in place and will continue to provide effective contraception if ultrasound confirms appropriate intrauterine positioning and the patient is not pregnant. 2
• Counsel the patient that the device is functioning correctly despite non-visible strings. 2
• Advise the patient to return promptly for heavy bleeding, cramping, pain, abnormal vaginal discharge, or fever. 1, 2

Malpositioned IUD (Low-Lying or Extending into Cervix)

• Remove the IUD as soon as possible if it is low-lying, extending into the cervix, or embedded in the myometrium, especially when associated with pelvic pain. 1
• If strings are visible or can be safely retrieved, removal can proceed without additional imaging when previous ultrasound already confirmed malposition and the patient has persistent symptoms. 6, 1
• If strings are not visible and the IUD cannot be safely retrieved, refer for ultrasound-guided removal. 6

Perforated IUD

• The IUD must be removed as soon as possible if perforation is confirmed, as serious complications including bowel or kidney damage and peritonitis can occur. 2, 7
• Laparoscopic removal is typically required for perforated devices. 2, 7
• The incidence of perforation is 0.12-0.68 per 1000 insertions, and many patients are asymptomatic at diagnosis. 7

Critical Pitfalls to Avoid

• Never assume expulsion without imaging confirmation. Missing strings can indicate perforation, which requires urgent intervention even in asymptomatic patients. 5
• Do not leave a malpositioned IUD in place if the patient has symptoms. The CDC emphasizes prompt removal when malposition is associated with pelvic pain, as symptom resolution rates are significantly higher with removal. 6, 1
• Always rule out pregnancy before proceeding. If the patient is pregnant, management changes entirely—removal should be attempted if possible to reduce risks of spontaneous abortion, septic abortion, preterm delivery, and infection. 2

Post-Management Counseling

• Discuss alternative contraceptive methods if the IUD is removed. 1, 2
• Schedule follow-up to ensure symptom resolution if removal was performed. 1
• Reinforce warning signs requiring immediate care: heavy bleeding, severe cramping, pain, abnormal vaginal discharge, or fever. 1, 2