What's the difference between perimenopause and menopause?

Perimenopause is the transitional phase before official menopause. In this phase (typically ages 42-50), ovaries begin producing estrogen inconsistently - menstrual cycles become irregular, longer or shorter, heavier or lighter. Symptoms like hot flushes, sleep difficulty, and mood changes typically start during perimenopause. Menopause itself is a specific point - definition is 12 consecutive months without menstruation. You only know you've reached menopause retrospectively, after the 12-month no-period window completes. After this point, you're technically in postmenopause for the rest of your life. For Malaysian women, perimenopause typically lasts 4-10 years, with official menopause at 49-51. Many symptoms people call 'menopause' actually occur in the perimenopause phase - when estrogen fluctuates most. Per Persatuan Obstetrik dan Ginekologi Malaysia guidelines, diagnosis is clinical - based on menstrual patterns and symptoms, not a single blood test.