When is it appropriate to replace a Mirena (levonorgestrel intrauterine system) in a woman?

When to Replace Mirena IUD

Mirena should be replaced at 8 years for contraception, or at 5 years if being used specifically for heavy menstrual bleeding treatment, though contraceptive efficacy extends well beyond the original FDA approval period.

Duration of Use Based on Indication

For Contraception

• The 52-mg levonorgestrel IUD (Mirena) maintains high contraceptive efficacy through 8 years of use, with a cumulative failure rate of only 0.68% during years 6-8 and Pearl Indexes of 0.34,0.40, and 0.00 for years 6,7, and 8 respectively 1
• The FDA originally approved Mirena for 5 years, but extended approval now covers up to 7 years, with clinical evidence supporting use through 8 years 2, 1
• Women aged 18-35 who wish to continue contraception can safely keep their Mirena for up to 8 years without replacement, maintaining excellent efficacy and user satisfaction (98.7% satisfaction at 8 years) 1

For Heavy Menstrual Bleeding (Menorrhagia)

• When prescribed specifically for heavy menstrual bleeding treatment, Mirena should be replaced at 5 years, as this is the only duration formally evaluated and proven effective for this therapeutic indication 2, 3
• The 52-mg device achieves a 71-95% reduction in menstrual blood loss and is recommended as first-line medical treatment by the American College of Radiology 2, 4
• Only the 20 µg/day levonorgestrel devices (Mirena and Liletta) have established evidence for treating abnormal uterine bleeding; lower-dose devices like Skyla have not been studied for this indication 2

Clinical Decision Algorithm

Step 1: Identify Primary Indication

• If contraception is the sole or primary goal: Plan replacement at 8 years 1
• If heavy menstrual bleeding treatment is the indication: Plan replacement at 5 years 2, 3
• If both contraception and bleeding control are needed: Use the 5-year timeframe for therapeutic efficacy, though contraceptive protection continues beyond this 2, 1

Step 2: Assess Device Function Before Scheduled Replacement

• Confirm device position by checking for visible strings at routine visits 4
• If strings are not visible, obtain pelvic ultrasound to evaluate for displacement or expulsion 4
• Rule out pregnancy with urine testing if there is any clinical suspicion, though failure rates remain extremely low even in extended use 4, 1

Step 3: Evaluate for Early Replacement Indications

Replace Mirena before the scheduled timeframe if:

• Device expulsion occurs (higher risk in women with uterine fibroids at 11% vs 0-3% in women without) 5
• Pregnancy occurs with device in situ 1
• Patient develops contraindications such as current breast cancer, cervical or endometrial cancer awaiting treatment, or acute pelvic inflammatory disease 5, 4
• Unacceptable bleeding patterns persist despite reassurance and management, and the patient requests removal 5, 4
• Patient desires pregnancy (return to fertility is rapid, with 77.4% achieving pregnancy within 12 months of removal) 1

Important Clinical Considerations

Bleeding Pattern Changes Do Not Indicate Device Failure

• Bleeding pattern changes do not correlate with contraceptive failure, as the mechanism of contraception remains independent of bleeding patterns 2
• During extended use beyond 5 years through 8 years, women report decreased bleeding or spotting days, with approximately half experiencing amenorrhea or infrequent bleeding 1
• If bleeding is heavy, prolonged, or concerning, evaluate for pathology including pelvic exam, STI screening, and pelvic ultrasound to assess for structural abnormalities 4

Management of Unacceptable Bleeding

• Provide reassurance that bleeding changes are common and do not indicate contraceptive failure if device is properly positioned and no pathology is found 4
• Offer symptomatic management with NSAIDs for 5-7 days during bleeding episodes, or hormonal treatment with combined oral contraceptives or estrogen for 10-20 days if medically eligible 4
• If bleeding remains unacceptable despite management, discuss options for early removal with alternative contraception, or continuing use with understanding that contraceptive protection remains intact 4

Special Populations

• For women with cardiovascular disease (ischemic heart disease, stroke, hypertension, or venous thromboembolism), Mirena is generally acceptable with benefits outweighing theoretical risks, and standard 7-8 year duration applies 2
• For nulliparous women and adolescents, Mirena is safe and does not cause tubal infertility, with the same replacement schedule as parous women 2, 4
• For HIV-infected individuals, benefits of IUD use generally outweigh theoretical or proven risks 2, 4

Common Pitfall to Avoid

Do not remove Mirena prematurely at 5 years in women using it solely for contraception who are satisfied with the device and wish to continue—this unnecessarily exposes them to reinsertion risks and costs when the device maintains excellent efficacy through 8 years 1