What approach should be taken for hormone testing in a woman with an Intrauterine Device (IUD) experiencing menopausal symptoms?

Hormone Testing in Women with IUDs During Menopause

Hormone testing (FSH, estradiol) is generally unreliable and not recommended for diagnosing menopause in women using levonorgestrel-releasing IUDs, as the progestin can suppress FSH levels and alter bleeding patterns that would otherwise signal menopausal transition.

The Core Problem with Hormone Testing in IUD Users

The levonorgestrel IUD fundamentally interferes with the typical markers used to diagnose menopause:

• Bleeding patterns become unreliable indicators because the LNG-IUD causes endometrial suppression, leading to amenorrhea or oligomenorrhea in approximately 50% of users by 2 years of use 1, 2
• The device's local hormonal effects create strong suppression of endometrial growth, making the endometrium insensitive to ovarian estradiol, which obscures the natural menstrual changes that typically signal perimenopause 3
• Amenorrhea with an LNG-IUD is a device effect, not necessarily a sign of menopause, as the device itself causes many women to experience complete absence of periods 2, 4

Practical Approach to Menopause Diagnosis in IUD Users

Age-Based Strategy (Most Practical)

• For women over age 50-55 with an IUD: Assume menopause has likely occurred and manage symptoms empirically rather than relying on hormone testing 5
• The average age of menopause is approximately 51 years, making age a more reliable indicator than hormone levels in IUD users 5

Symptom-Based Management

Focus on clinical symptoms rather than laboratory values:

• Vasomotor symptoms (hot flashes, night sweats) can occur regardless of IUD use and indicate estrogen deficiency 6, 5
• Research shows no significant relationship between Mirena IUD use and menopausal symptoms, meaning symptoms that develop are likely genuine menopausal changes, not IUD-related 6
• Treat symptoms empirically with estrogen therapy if clinically indicated, rather than waiting for confirmatory hormone tests 5, 7

Optimal Management Strategy: LNG-IUD Plus Estrogen

The most effective approach is to continue the LNG-IUD and add systemic estrogen therapy for menopausal symptoms, creating a seamless transition through menopause:

• The LNG-IUD provides endometrial protection while systemic estrogen (gel, patch, or oral) treats vasomotor and other menopausal symptoms 5
• This combination allows smooth transition through menopause without interrupting contraception or endometrial protection 5
• High patient acceptance: In one study, 82% of perimenopausal women opted to continue this regimen, with average use extending 137 months 5
• Multiple benefits: Prevents pregnancy, treats menorrhagia if present, provides endometrial protection, and manages menopausal symptoms simultaneously 5, 7

When to Consider IUD Removal

If hormone testing is deemed absolutely necessary:

• Remove the IUD and wait 2-3 months before testing FSH and estradiol levels to allow the endometrium to recover from progestin suppression 3
• Check FSH levels: Persistently elevated FSH >25-30 IU/L suggests menopause, though this requires the IUD to be removed first
• This approach sacrifices contraception and endometrial protection, making it less desirable than empiric symptom management 5

Key Clinical Pitfalls to Avoid

• Do not interpret amenorrhea in an LNG-IUD user as definitive menopause without considering the device's suppressive effects 2, 4
• Do not delay symptom treatment while pursuing unreliable hormone testing 5, 7
• Do not remove a functioning IUD solely for diagnostic purposes when symptom-based management is more practical 5
• Remember that BMI affects symptoms: Higher BMI increases likelihood of hot flashes and night sweats independent of IUD use 6

Duration of IUD Use Through Menopause

• The 52-mg levonorgestrel IUD (Mirena) is FDA-approved for 5 years but data suggest effectiveness up to 7 years 2
• IUDs can be continued through menopause and serve dual purposes of contraception during perimenopause and endometrial protection when combined with estrogen therapy 5, 7
• Contraception remains necessary until confirmed postmenopausal status, as perimenopausal women face considerable risk of unintended pregnancy 5, 7