1) The document discusses the clinical features, differential diagnosis, and investigations of menopause. It describes various symptoms that can occur during perimenopause and menopause such as hot flashes, sleep issues, mood changes, and changes to the skin, hair, cardiovascular and genitourinary systems. 2) Differential diagnoses are provided for different symptoms. Investigations like hormonal tests and imaging can help determine if symptoms are due to menopause or other potential medical conditions. 3) Natural menopause is diagnosed if a woman over age 40 has 12 months of amenorrhea accompanied by menopausal symptoms and elevated FSH levels on two separate occasions.