Can an infected Intrauterine Device (IUD) cause symptoms?

Can an Infected IUD Cause Symptoms?

Yes, an infected IUD can cause symptoms, but the infection risk is primarily limited to the first 21 days after insertion, and most IUD-related infections present as pelvic inflammatory disease (PID) with lower abdominal pain, fever, abnormal vaginal discharge, and cervical motion tenderness. 1

Understanding IUD-Related Infection Risk

The critical distinction is timing and mechanism:

• The highest infection risk occurs within the first 21 days post-insertion, after which IUDs do not increase rates of sexually transmitted infections or PID above baseline 2, 1
• The overall infection risk is low (approximately 5.9% or less), with the majority of cases occurring within the first 3 months 1
• IUDs themselves do not cause infection—they can facilitate upward spread of existing cervical bacteria (particularly Chlamydia trachomatis and Neisseria gonorrhoeae) during the insertion process 2

Clinical Presentation of IUD-Related Infections

When an IUD becomes associated with infection, symptoms typically include:

• Lower abdominal or pelvic pain (most common presenting symptom) 2
• Fever (particularly concerning if within 21 days of insertion) 1
• Abnormal vaginal discharge (purulent or foul-smelling) 2
• Cervical motion tenderness on examination 2
• Abnormal vaginal bleeding (though this alone is not specific for infection) 2

The CDC guidelines classify current PID with an IUD in place as Category 4 for insertion (contraindicated) but Category 2 for continuation, meaning the IUD usually does not need to be removed if the woman wishes to continue using it during PID treatment 2.

Microbiology of IUD-Associated Infections

The organisms involved are typically:

• Chlamydia trachomatis (recovered from 5-39% of women with PID) 2
• Neisseria gonorrhoeae (cervical isolation rates 27-80% in PID cases) 2
• Mixed anaerobic and aerobic bacteria including Bacteroides, Peptostreptococcus, Gardnerella vaginalis, and E. coli (found in 25-50% of acute PID cases) 2
• Actinomyces species (uncommon, typically only with prolonged IUD use beyond recommended removal time) 2, 3

Importantly, cultures of removed IUDs in asymptomatic women commonly grow bacteria (94.5% positive in one study) consisting of normal flora that do not cause PID 4. This means bacterial colonization of the IUD does not equal infection.

Management Algorithm

For suspected IUD-related infection:

1. Assess timing: Fever/symptoms within 21 days of insertion are most concerning for insertion-related infection 1

2. Test for STIs: Screen for Chlamydia and Neisseria gonorrhoeae 2

3. Initiate appropriate antibiotics for PID without waiting for culture results 2

4. The IUD does NOT need to be removed unless:

   • The patient requests removal 2
   • No clinical improvement after 72 hours of appropriate antibiotic therapy 1
   • Evidence shows clinical course does not differ whether IUD is removed or left in place during PID treatment 2

5. Continued IUD use depends on the woman's informed choice and current risk factors for STIs 2

Critical Caveats

• Asymptomatic cervical infections at insertion: Women with asymptomatic Chlamydia or gonorrhea at the time of IUD insertion have a low absolute risk of subsequent PID, though higher than uninfected women 2
• Screening can be performed on insertion day in asymptomatic high-risk women, with treatment provided subsequently without IUD removal 2, 1
• Culture of removed IUDs in asymptomatic women is not recommended, as bacterial colonization is common and does not indicate infection requiring treatment 4
• HIV infection is not a contraindication to IUD use, though women with AIDS should be closely monitored for pelvic infection 2