How to Track Your Cycle Accurately
In this guide
Why track
The 4 things to log
Detecting ovulation
Patterns that matter
When to see a doctor
FAQ
Why track at all
Three reasons: detect changes early (irregularities point to thyroid, PCOS, perimenopause, or stress), plan for life events (travel, training, conception or contraception), and self-knowledge (mood, energy, and productivity often follow cycle phases more than people realize).
The 4 things to log every day (or at least each phase)
- Period days and flow. Mark start day, duration, and intensity (light/medium/heavy/spotting).
- Cervical mucus. Dry, sticky, creamy, or egg-white-stretchy. Mucus quality shifts predict ovulation 1–3 days out.
- Mood and energy on a 1–5 scale.
- Notable symptoms: cramping, bloating, headache, breast tenderness, libido.
Detecting ovulation
Three methods, in order of reliability:
- LH urine tests (ovulation predictor kits) detect the surge ~24–36 hours before ovulation. Most accurate signal short of blood work.
- Basal body temperature (BBT) rises 0.3–0.6°C after ovulation. Confirms after-the-fact.
- Cervical mucus pattern peaks at "egg-white" texture at fertile peak.
Calendar math (day 14 of a 28-day cycle) is the least reliable; real ovulation moves with stress, travel, illness.
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Patterns that tell you something
- Cycles < 21 days or > 35 days repeatedly — suggests anovulation; consider PCOS, thyroid, or hypothalamic causes.
- Variable cycle length > 7 days between cycles — common in late perimenopause.
- Severe pain that limits activity — suggests endometriosis or adenomyosis. Worth evaluation.
- Heavy bleeding (changing protection more than every 2 hours, clots larger than a quarter) — rule out fibroids, anemia.
- Mid-cycle bleeding — usually benign but worth a clinical conversation if recurrent.
When to see a doctor
- Periods stop for 3+ consecutive cycles outside pregnancy/breastfeeding/menopause
- Heavy bleeding with fatigue or shortness of breath (possible anemia)
- Severe pelvic pain
- Spotting between periods that recurs over multiple cycles
- Pain with sex (deep, persistent)
Frequently Asked Questions
How many cycles before I can see a pattern?
Three full cycles minimum, six is better. Hormones fluctuate, and one outlier shouldn't change your model.
Should I track during perimenopause?
Yes — tracking helps you understand what is normal for you and when to seek evaluation.
What about the moon?
No biological mechanism; lunar correlation has not survived rigorous study.