When perimenopause tends to begin
People ask this when something in their cycle or sleep changes and they want to know if it is early, late, or normal. A reliable answer starts with current sources and your own record.
Where to find current figures
Check the federal drug regulator's menopause page for consumers and a government women's health office's menopause guide for current figures and definitions, then compare them with your own record.
Keeping your own cycle record
An age matters less than your own pattern. Keep a simple record of your cycle dates, how long bleeding lasts, how you sleep, and any changes in mood or temperature. Write down the date a change began and what else was happening, such as a move, a new job, or a new medicine.
If you are on a hormonal medicine or a device that affects your cycle, say so up front and ask how it affects your record. A clinician can tell you how to read your record.
Setting the sources beside your notes
Read both pages, then compare what they say with your own record. If your changes began earlier than the sources describe, or they are disruptive, book a visit and bring your notes. Ask what testing, if any, makes sense and what a sensible follow-up schedule looks like.
Why a record does not set a date
Tracking your own pattern shows a clinician what is changing and does not date your transition for you. Whether your symptoms point to perimenopause is a question for a licensed clinician.