What are the complications associated with intrauterine device (IUD) use?

Complications of IUD Use

IUDs are highly safe and effective contraceptives with typical failure rates <1%, but complications include pelvic infection (primarily within 21 days of insertion), expulsion (2-5%, higher in younger women), insertion pain, menstrual changes, uterine perforation, and pregnancy-related complications if conception occurs with the device in place. 1, 2

Infection-Related Complications

Pelvic Inflammatory Disease (PID)

• Risk is confined to the first 21 days after insertion - beyond this period, IUDs do not increase rates of STIs or PID 1
• Absolute risk remains low even with STI present at insertion, though higher than in women without STI 2
• PID can be treated with the IUD in place - removal is not routinely necessary if the patient improves with appropriate antibiotics 1, 2, 3
• Rate of PID: approximately 3.5 per 1000 women-years for copper IUDs 4

Key Management Points for PID:

• Treat with appropriate antibiotics
• Reassess in 24-48 hours
• Remove IUD only if no clinical improvement or if patient desires discontinuation 3
• Clinical outcomes do not differ between IUD removal versus retention during PID treatment 2

Mechanical Complications

Expulsion

• Occurs in <5% of women overall 1
• Higher rates in younger/nulliparous women and adolescents 1
• Rates for copper IUDs: 0-1.2% per year 4
• Rates for levonorgestrel IUDs: 0-0.2% per year 4
• Increased expulsion with uterine fibroids (11% vs 0-3% in women without fibroids) 2
• Higher expulsion rates with immediate postpartum insertion, though this remains an acceptable practice 1

Uterine Perforation

• Rare complication, primarily occurs at insertion
• Risk increased with cervical/endometrial cancer, distorted uterine cavity 2
• Anatomic abnormalities that distort the uterine cavity represent an absolute contraindication (Category 4) 2

Pregnancy-Related Complications

If Pregnancy Occurs with IUD in Place:

• Evaluate immediately for ectopic pregnancy - while absolute risk is extremely low due to IUD effectiveness, relative likelihood of ectopic increases greatly if pregnancy occurs 3, 2
• Pregnancy rate: 0.6-1.1% per year for copper IUDs 4
• Increased risk for spontaneous abortion (including life-threatening septic abortion) and preterm delivery if IUD remains 3

Management Algorithm:

1. If strings visible: Remove IUD as soon as possible by gentle traction 3
2. If strings not visible: Consider ultrasound to locate device; if intrauterine and cannot be safely retrieved, counsel patient about risks 3
3. Advise patient to seek immediate care for heavy bleeding, cramping, pain, abnormal discharge, or fever 3

Menstrual and Pain Complications

Insertion Pain

• >50% of young nulliparous women report moderate to severe pain with insertion 1
• Paracervical or intracervical blocks significantly reduce insertion pain 5
• Post-procedure: NSAIDs scheduled for 24-72 hours 5

Menstrual Changes

• Copper IUD: May intensify dysmenorrhea and increase menstrual bleeding 2
• Levonorgestrel IUD: Typically reduces dysmenorrhea and menstrual blood loss; amenorrhea occurs in 7-11% 2, 6
• Heavy menstrual bleeding: 4.85-15.69% of users 6
• Pelvic pain: 11-14% of users 6
• Menstrual problems are the leading cause of IUD removal (approximately one-third removed within first year) 4

Absolute Contraindications (Category 4)

Do not insert IUD if:

• Current pregnancy 2
• Current purulent cervicitis, gonorrhea, or chlamydia infection 1, 2, 1
• Current PID or other pelvic infection 1, 2
• Puerperal sepsis 2
• Distorted uterine cavity incompatible with insertion 2
• Unexplained vaginal bleeding suspicious for serious pathology (until evaluated) 2
• Current breast cancer (for levonorgestrel IUD only) 2

Important Clinical Caveats

• Past PID is NOT a contraindication to IUD use 1, 2
• HIV infection and immunosuppression are NOT contraindications 1, 2
• Nulliparity is NOT a contraindication - IUDs do not cause tubal infertility 1
• STI screening can be performed on day of insertion; treatment provided afterward without IUD removal 1
• Continuation rates in adolescents exceed other hormonal methods despite higher expulsion rates 1
• Failed insertion occurs in 1.8-20% of cases; consider misoprostol, ultrasound guidance, or local anesthesia for reattempt 5