Evidence check: FT3 in the context of Wechseljahre

FT3 (free triiodothyronine) is a thyroid hormone typically used to assess thyroid dysfunction (e.g., hyperthyroidism), not as a specific marker for menopause. During menopause, hormonal shifts can cause symptoms similar to thyroid issues (fatigue, weight changes, mood swings). However, there is no strong evidence that FT3 alone or in combination reliably indicates menopausal status or guides hormone therapy. Current guidelines recommend measuring FSH, estradiol, and possibly TSH for menopause assessment, not FT3. Marketing FT3 as a 'menopause marker' in consumer tests is misleading. The evidence base is weak, relying on clinical practice rather than controlled trials. Caveat: Isolated FT3 values without TSH and free T4 can lead to misdiagnosis.