The short version
Perimenopause is the transition phase before menopause. It’s when your body’s hormone levels — especially oestrogen and progesterone — begin to fluctuate more unpredictably. This can trigger a wide range of physical and emotional symptoms, from hot flashes and night sweats to brain fog, anxiety, and joint pain.
Menopause itself is a single point in time: 12 consecutive months without a period. Everything before that point is perimenopause. Everything after is post-menopause.
When does it start?
Most people enter perimenopause in their mid-40s, but it can start as early as the late 30s. The transition typically lasts 4 to 8 years, though for some people it’s shorter and for others it stretches beyond a decade.
There’s no single test that confirms you’re in perimenopause. Hormone levels fluctuate too much day-to-day to be reliable. Most doctors diagnose it based on symptoms, age, and menstrual history — which is exactly why tracking matters.
What’s actually happening in your body?
During your reproductive years, your ovaries produce oestrogen and progesterone in a fairly predictable cycle. In perimenopause, this rhythm breaks down:
- Oestrogen doesn’t just decline — it surges and crashes unpredictably. Some months you may have higher levels than ever before, followed by sharp drops.
- Progesterone tends to decline more steadily as ovulation becomes less frequent.
- FSH (follicle-stimulating hormone) rises as your body tries harder to stimulate the ovaries.
These hormonal swings affect almost every system in your body. Oestrogen receptors exist in your brain, bones, heart, gut, skin, and urinary tract — which is why perimenopause symptoms can seem so varied and unconnected.
Common symptoms
Perimenopause can bring over 40 recognised symptoms. The most common include:
- Vasomotor: Hot flashes, night sweats, heart palpitations
- Cognitive: Brain fog, difficulty concentrating, memory lapses
- Emotional: Anxiety, mood swings, irritability, low mood
- Sleep: Insomnia, waking at 3am, unrefreshing sleep
- Physical: Joint pain, muscle tension, headaches, fatigue
- Reproductive: Irregular periods, heavier or lighter flow, vaginal dryness
See our full symptom guide for detailed descriptions of each symptom Sulu helps you track.
Why tracking helps
One of the most frustrating things about perimenopause is how hard it is to explain what you’re experiencing. Symptoms come and go. Some weeks are fine; others are overwhelming. By the time you see your doctor, you’re trying to reconstruct months of vague recollections.
A daily symptom record changes that. It gives you — and your doctor — a clear picture of what’s happening over time. You can spot patterns you wouldn’t see otherwise: that your brain fog is worse after bad sleep, that your anxiety spikes mid-cycle, that joint pain correlates with stress.
That’s what Sulu is for. A 30-second daily check-in that builds into a clear, shareable record.
What can you do about it?
Perimenopause is a natural transition, not a disease. But that doesn’t mean you have to suffer through it. Options include:
- Hormone replacement therapy (HRT): The most effective treatment for many symptoms. Read our guide to HRT.
- Lifestyle changes: Exercise, stress management, sleep hygiene, and reducing alcohol and caffeine can all make a meaningful difference.
- Supplements: Some women find relief with magnesium, vitamin D, or herbal supplements. See our supplement tracking page.
- Talking to your doctor: The first step is having a productive conversation — and a symptom record makes that much easier.
The bottom line
Perimenopause is a significant biological transition that affects most women for years. It’s not “just stress” or “getting older.” The symptoms are real, they’re caused by measurable hormonal changes, and there are effective treatments available.
The first step is understanding what’s happening. The second is having a clear record to share with your doctor. That’s where Sulu comes in.
