What lab tests are used to diagnose menopause?

Laboratory Tests for Diagnosing Menopause

The primary laboratory tests for diagnosing menopause are follicle-stimulating hormone (FSH) and estradiol levels, which should be interpreted in the context of clinical symptoms and menstrual history. 1

Primary Laboratory Tests

• Follicle-stimulating hormone (FSH): Elevated levels indicate declining ovarian function and are a key marker for menopause assessment 1
• Estradiol: Low levels, when combined with high FSH, help confirm menopausal status 1
• Luteinizing hormone (LH): May be checked as clinically indicated to provide additional information about ovarian function 1
• Prolactin: Should be measured when clinically indicated to rule out other causes of menstrual irregularity 1

Diagnostic Criteria for Menopause

For women under age 60, menopause can be confirmed by:

• Amenorrhea for 12 or more months AND
• FSH and estradiol in the postmenopausal range 2, 1

Special Considerations

• Single measurements are unreliable: During the menopausal transition, hormone levels fluctuate markedly, making single measurements unreliable guides to menopausal status 3, 4
• Serial testing: For perimenopausal women who become amenorrheic and later develop bleeding, serial estradiol levels can help determine if ovarian function has returned 2
• Anti-Müllerian hormone (AMH): May provide additional information on ovarian reserve status, though normative data are limited 2, 1
• Women on tamoxifen: FSH and estradiol should be measured to confirm menopausal status in women under age 60 2, 1
• Women on LHRH agonists/antagonists: It is not possible to accurately determine menopausal status in these women 2

Limitations of Laboratory Testing

• FSH levels can fluctuate significantly during perimenopause, with postmenopausal levels sometimes returning to the normal reproductive range 5
• In a study of regularly cycling women over age 45,7% had FSH levels typical of postmenopause, and 39% had elevated levels despite regular cycles 5
• Serum FSH and estradiol are not accurate enough by themselves to diagnose perimenopause 4
• Clinical diagnosis based on menstrual history and age remains the most reliable approach 4

When to Order Laboratory Tests

Laboratory tests for menopause should be ordered when:

• Women present with irregular menstrual cycles 1
• Women experience vasomotor symptoms (hot flashes, night sweats) 1
• Before initiating hormone therapy 1
• After chemotherapy to assess ovarian function 2, 1
• Women with hysterectomy but intact ovaries need menopausal status determined 1

Interpreting Results

• Postmenopausal range: FSH >35 mIU/mL is generally considered in the postmenopausal range 6
• Confirmation: At least two consecutive high FSH evaluations are recommended to confirm menopausal status, as 40.6% of women with high FSH may have normal levels in subsequent testing 6
• Age consideration: FSH measurements are most useful in women ≥50 years old due to greater likelihood of being in postmenopause 6

Common Pitfalls

• Relying on a single FSH or estradiol measurement to determine menopausal status 5, 4
• Assuming amenorrhea after chemotherapy indicates menopause (ovarian function may still be intact or resume) 2
• Using FSH as the sole diagnostic criterion in women on hormonal medications 2, 1
• Failing to consider that thyroid disease can affect menstrual patterns and should be ruled out before attributing symptoms to menopause 2

Remember that laboratory testing should complement, not replace, clinical evaluation of menopausal status based on age, menstrual history, and symptoms.