Most women expect perimenopause to arrive in their late 40s — but for many, the first subtle signs appear years earlier. Understanding the typical timeline can help you recognise what is happening in your body and seek support sooner.
The Average Age — and Why It Varies
In Australia, the average age of menopause (the official end point) is 51–52 years. Since perimenopause typically lasts 4–10 years, most women begin the transition between ages 40 and 47. However, this is an average — the range is wide.
💡 📊 Key statistics: Premature menopause (before 40) affects 1 in 100 Australian women. Early menopause (ages 40–45) affects approximately 5%. For most women, perimenopause begins between 45 and 50.
Early Signs in Your Late 30s
Some women notice the first signs of perimenopause as early as their late 30s. These early changes are often subtle and easy to attribute to stress or lifestyle factors.
- Your menstrual cycle shortens — periods coming every 24–26 days instead of 28
- Premenstrual symptoms (PMS) become more intense than before
- You notice occasional night sweats or disrupted sleep
- Mood changes — feeling more anxious or irritable around your period
- Breast tenderness that feels different from before
Signs in Your Early 40s
For most women, perimenopause becomes more noticeable in the early 40s. Hormonal fluctuations become more pronounced and symptoms more consistent.
- Cycles becoming irregular — varying in length from month to month
- Occasional missed periods
- Hot flushes beginning — even mild ones
- Sleep becoming more disrupted
- Brain fog and difficulty concentrating
- Fatigue that does not improve with rest
Factors That Influence Timing
Several factors can influence when perimenopause begins for you. Genetics is the strongest predictor — if your mother entered menopause early, you are more likely to as well. Other factors include smoking (which can bring menopause forward by 1–2 years), certain medical treatments (chemotherapy, radiation), and surgical removal of the ovaries.
When to See Your GP
You should see your GP if you experience symptoms before age 40, if your symptoms are significantly affecting your quality of life, or if you simply want clarity. From July 2025, Australian women are eligible for a Medicare-rebated menopause health assessment — a dedicated appointment to discuss your symptoms and options.