How to know if you're in perimenopause
The diagnostic gold standard for women under 45 is not a blood test. Hormones swing too wildly week-to-week to be useful. What clinicians actually look for is a pattern: a persistent change in your cycle plus at least one classic symptom.
The two-criterion rule
STRAW+10 (the international staging system) flags early perimenopause when:
- Your cycle length varies by 7 or more days from your usual.
- Plus any new symptom: hot flushes, night sweats, mood swings, sleep loss, brain fog.
What gets mistaken for perimenopause
- Thyroid disease — fatigue, weight gain, mood changes overlap heavily. Ask for TSH + free T4.
- Iron deficiency — heavy periods can hide it. Ask for ferritin.
- PMDD — premenstrual mood symptoms that resolve when bleeding starts.
- Burnout / chronic stress — disrupts cycles and sleep without hormonal cause.
When to see a doctor now
Bleeding between periods, periods closer than 21 days, periods longer than 7 days, or any bleeding after 12 months without a period — get checked. These are not normal perimenopause patterns.
Track symptoms with a coach who actually gets perimenopause.
Lila connects symptoms, food and sleep so you can see what's hormonal and what's not.