Cycle × body · 5 min
Menstrual cycle phases: a short cheat sheet
The menstrual cycle is conventionally split into four phases. The boundaries are soft — they're not partitions, just shifting hormone ratios. Below: what each phase does physiologically and what people who track their own data most often report. No "you should feel", no pink coaching.
Menstruation (day 1–5)
Estrogen and progesterone are at their lowest. The uterus sheds its lining.
- Often: lower energy, increased need for sleep, lower abdomen and back pain.
- Sometimes: clearer head towards the end of bleeding, fewer mood swings than in luteal.
- Data usually shows: lower energy scores on day 1–2, normalising from day 3–4.
Follicular phase (day 6–13)
Estrogen rises. A follicle in the ovary prepares for ovulation.
- Often: rising energy, better tolerance of stimuli, more openness to new things.
- Sometimes: faster recovery after short sleep.
- Data usually shows: more stable mood, less irritability, lower intensity of negative emotions.
Ovulation (day 13–16)
Estrogen peaks, brief testosterone surge, egg release.
- Often: EWCM (clear, stretchy mucus), rise in libido, sometimes one-sided ovulation pain.
- Sometimes: clearer skin, more confidence, better focus.
- Data usually shows: high energy and mood, low irritability — often the best 2–3 days of the cycle.
Luteal phase (day 17–28)
Progesterone rises, then drops in the final days. Estrogen has a second, lower peak mid-phase.
- Often in the first half: calm, more pull towards withdrawal, thicker mucus.
- Often in the second half (5–10 days before period): PMS — irritability, lower mood, higher sensitivity to stimuli, appetite shifts, sleep problems.
- Data usually shows: drop in energy in the last week, rise in irritability, larger within-day mood swings.
What this cheat sheet doesn't replace
Population averages aren't your cycle. For one person ovulation brings energy, for another — sharp pain. For one PMS is a quiet week, for another — three days of chaos. The point of tracking your own data across 2–3 cycles is seeing how phases actually land in your body — not in the body of the average textbook woman.
What to do with this
Nothing, if you don't want to. Just knowing which phase you're in and what's typical there is often enough for harder days to stop being "for no reason". The rest is observation — what repeats for you in luteal, what doesn't.