Why a wrong date is worth fixing
MiniCycle estimates cycle length from saved period starts, using up to the latest 12 starts and a median-style calculation. That reduces the influence of one unusual interval, but a correction can still change the result depending on how many records you have and which value changed.
The most recent start also anchors future dates. Correcting it generally moves the next-period, ovulation, and fertile-window estimates, but the shift is not guaranteed to equal the same number of days because the cycle-length estimate may change too.
Moving a period start to the right day
Tap the correct day on the calendar and mark a period start. If it is within 7 days of an existing start, MiniCycle offers to change that period rather than adding a second one. Confirm the Period change alert to apply the correction.
The end date is filled from the current period-length setting or automatic estimate. If it does not match what happened, select the actual last day and update the end next.
Adjusting an end date
Tap the actual last day of the period and mark a period end. Two rules apply. The end cannot fall before the start, and a single record can span at most 14 days, counting the start day itself. Outside those bounds the app shows a short message instead of saving.
You do not pick a record from a list; you pick a day. The end attaches to the record that contains that day, or to one whose start falls within the previous 14 days. If more than one record qualifies, the one with the most recent start date wins.
Deleting a record that should not exist
Select any date inside the period you want to remove. In the detail card for that period, tap the trash button and confirm the deletion. MiniCycle does not use a press-and-hold gesture for this action.
Reset records in Settings clears every period and daily log. Use the trash button for one incorrect period; use the full reset only when you intend to erase all records.
What happens after you fix a date
The app recalculates estimates and reschedules local notifications from the corrected records. It also writes the shared data and requests a widget reload. iOS decides when the widget redraws, so the home-screen change can take a little longer.
Records are stored on the device by default. If iCloud Sync is enabled, MiniCycle also attempts to synchronize the corrected state through CloudKit.
What corrections can and cannot do
A correction makes your record match your body. It cannot make predictions exact. An analysis of more than 600,000 real-world cycles found that cycle length varies from month to month for most people, which is why MiniCycle keeps re-estimating from recent records instead of trusting any single month. Corrected data gives the estimate better inputs, not certainty.
The dates on the calendar remain reference information for planning. They are not medical advice, contraception, or a way to confirm or rule out pregnancy. If the bleeding pattern itself is what concerns you, that is a conversation for a clinician, and an accurate record of dates is a useful thing to bring along.
MiniCycle for iPhone
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MiniCycle is built for a clean iPhone period calendar, local records, simple statistics, and a home screen widget.
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References
- Mayo Clinic. Menstrual cycle: What's normal, what's not.
- Bull JR, Rowland SP, Scherwitzl EB, et al. Real-world menstrual cycle characteristics of more than 600,000 menstrual cycles. npj Digital Medicine. 2019.
- Jain V, Munro MG, Critchley HOD. Contemporary evaluation of women and girls with abnormal uterine bleeding: FIGO Systems 1 and 2. Int J Gynecol Obstet. 2023.
- MiniCycle Privacy Policy.