Your cycle day with phase, a forecast of your next period and an honest look at regularity — only if you agree.
Three things the app works out from your entries. The sources are listed at the bottom of the page.
From your last period start and your average length, the app shows which day you're on and which phase — as a window, never as a single day.
Example: a 29-day cycle
Ovulation is counted back from the expected period start — the first half varies too much to rely on.
From two logged period starts, the app predicts when the next one will come — or how long it's been overdue.
Cycles from 15 to 90 days count — longer gaps are usually a break in logging. In an analysis of over 600,000 cycles, the average was 29.3 days.4
The app rates how much your cycles vary — following the stages of the expert panel STRAW+10.5
How the app rates it
If your cycles start varying or a long pause occurs, buttons for typical signs of menopause appear on their own — not before.
Period, flow, body and wellbeing — one button each. Also backdated, if you log it later.
The analysis shows what came up most often in the last 28 days.
An analysis of 78 studies found only a very small difference in performance across the cycle.1 That doesn't make a fixed rule — but it does say: listen to yourself.
No phase forces you to do less. If you feel more tired, you can take that seriously.
Cycle data is among the specially protected health data. The area only stores anything once you explicitly agree.
Legal basis: Art. 9 GDPR and Art. 5 Swiss FADP — explicit consent to the processing of health data.
Women who menstruate need more iron. If you've logged a period in the last 60 days, the Blood values area recommends also measuring ferritin.2
Ferritin shows how much iron your body has stored. What makes sense for you is up to your doctor.
A ring shows where you are right now. Below are the same tiles as in the Cycle area of the app.
Day 26 of 29
Example: period on days 1 to 5, ovulation window on days 13 to 17. The dot marks today. The app expects the next period on 6 November.
How long each of your cycles was, as bars side by side. In an analysis of more than half a million cycles the average was 29.3 days — with a wide spread.4
Only appears if you choose the topic or your cycles vary a lot. Experts divide the transition into stages based on bleeding patterns.
Ask about your cycle. The coach knows your cycle day and links it to sleep, training and iron.
The app already calculates these connections today. A connection is not a cause — but it shows you where to look.
On days 1 to 5, the Sleep area points out that nights often feel worse — even though length and structure stay the same.3
If you've logged a period in the last 60 days, the Blood values area also recommends a ferritin value.
Your coach knows: according to a meta-analysis, performance differs only slightly across the cycle phases. So it won't change your training plan because of the phase alone — how you feel matters more.6
With periods, the German Nutrition Society (DGE) recommends 16 mg of iron a day (men 11 mg). If your ferritin is low, the coach first suggests iron-rich foods and vitamin C — supplements last.
A review of 78 studies found only a trivial difference in performance across the cycle, if anything slightly lower at the start of the period. General rules cannot be derived from it. The authors recommend a personal approach: observe how you feel in which phase.1
The DGE recommends 16 mg of iron a day for women before menopause (11 mg for men). Menstruating women are expressly among the groups that should pay attention to their intake.2
The studies do not support a rule like “train less in this phase”. If you feel more tired in one phase, you can take that seriously, but no phase forces you to do less.1
A new article every Friday.
Sleep · HormonesMenopause and sleep: why the nights get shorterDuring menopause, up to sixty percent of women report sleep problems. It's not just about hot flushes. What changes hormonally, what is proven to help — and why one cause is almost always overlooked.Read more
Diagnostics · Blood testFerritin: Why this marker shows more than iron deficiencyFerritin is considered an iron storage marker — and is often not included in standard blood panels. Yet it has a dual character: as an inflammation marker it rises even when iron stores are simultaneously depleted.Read more
Exercise · CycleCycle and training: should you train according to your cycle? What the research really showsCycle-based training sounds logical: go all out in the first half, ease off in the second. But the major review studies find only tiny differences between phases. What really matters are your symptoms, your iron levels, your sleep, and a cycle that doesn't disappear.Read moreEvery statement comes with its source; the figures are taken from the linked studies and opinions (checked on 1 November 2026). This is context from the research, not a diagnosis and no substitute for medical advice.
Get YUTHI from the App Store — iPhone first, from November 2026.
