What is the Origin of MHT Efficacy Windows?

This concept arose directly from the re-analysis and long-term follow-up of major clinical trials, notably the Women's Health Initiative (WHI), which demonstrated that the risks of MHT, such as venous thromboembolism and coronary heart disease, are significantly lower when initiated earlier in the menopausal transition. This finding shifted clinical practice towards individualized, timely intervention.

What is the Mechanism of MHT Efficacy Windows?

The efficacy window is governed by the physiological state of the vascular system and other target tissues at the time of hormone initiation. Starting estrogen therapy early, when the vasculature is still healthy, appears to confer cardioprotective effects. Conversely, introducing estrogen to an older, potentially atherosclerotic vascular system may increase risk due to inflammatory or pro-thrombotic effects. Optimal timing maximizes the therapeutic effect on bone density, vasomotor symptoms, and quality of life.

MHT Efficacy Windows ∞ Area

MHT Efficacy Windows

Meaning

The clinically recognized timeframes during which Menopausal Hormone Therapy (MHT), which includes estrogen and progestogen replacement, provides the maximum benefit for symptom relief and chronic disease prevention with the lowest associated risk. The primary window is typically defined as the period close to the onset of menopause, generally within ten years or before age 60. Timing is a critical factor in determining the overall risk-benefit profile of MHT.