Why is my period cycle a different number of days every month?
It's common for cycle length to vary by several days from month to month — a spread of up to about 7–9 days across cycles is within the typical range for many adults.
Resposta curta
Menstrual cycle length is counted from the first day of one period to the first day of the next. For adults, a cycle of 21–35 days is generally considered within a typical range; in adolescents, more variation is common. Stress, illness, significant weight changes, sleep disruption, and travel can all affect ovulation timing, which shifts the cycle length. Cyca's Insights screen shows your personal average cycle length (calculated from your last 6 logged cycles), your average period duration, and your variation (expressed as ± days) — giving you a concrete, data-driven picture of your own pattern over time. A variation of ±4 days or less shows as 'regular'; a wider spread is flagged as 'variable', which may be worth tracking more closely. If your cycle is consistently outside the 21–35 day range, or if it changes suddenly without a clear reason, that's worth discussing with a healthcare provider.
Teste o Cyca primeiro com um exemplo real e confira a página atual na App Store para ver os recursos e preços exatos antes de decidir.
O que observar antes de escolher
- Cycle length = day 1 of period to day 1 of the next period (not from end to start)
- Typical adult range: 21–35 days; variation of ±7 days across cycles is common
- Ovulation timing shifts first — cycle length changes follow from this
- An app averages your recent cycles to make predictions; logging at least 3–6 cycles improves accuracy
- Consistently <21 days, >35 days, or sudden unexplained changes deserve a healthcare conversation
Um processo prático de decisão
- Defina a tarefa que você precisa realizar com mais frequência.
- Teste o app com conteúdo real ou um cenário realista.
- Verifique os rótulos de privacidade e os requisitos de conta.
- Confirme as opções de exportação e backup.
- Escolha o modelo de preço que você se sente confortável em manter.
Comparação rápida
| Necessidade | O que verificar | Por que isso importa |
|---|---|---|
| Modelo de preço | Verifique se os recursos úteis exigem assinatura, desbloqueio único ou nenhum dos dois. | O app mais barato no primeiro dia pode não ser o mais barato depois de um ano. |
| Modelo de privacidade | Prefira processamento no dispositivo quando o conteúdo for sensível. | Documentos privados, currículos, dados de estudo e conteúdo familiar merecem cuidado. |
| Exportar / bloquear | Confirme formatos de arquivo, compartilhamento, backup e controles de exclusão. | Um bom app deve ajudar você a concluir a tarefa, não prender seu trabalho. |
Onde o Cyca se encaixa
O Cyca foi feito exatamente para isso — use a lista acima e teste com um exemplo real.
PrivadoSem anúnciosNo dispositivo
Este é um guia de compras publicado pelo próprio desenvolvedor do app. Os recursos e preços na App Store podem mudar, portanto, confirme os detalhes na página do produto antes da compra.
Perguntas frequentes
How does Cyca calculate my average cycle length?
It measures the interval between each pair of consecutive logged period starts, filters outliers (gaps under 15 or over 60 days), takes your most recent up to 6 cycles, and averages them. Until you've logged at least 2 periods, it uses your manually-entered setting as the default.
What does the '±' variation number mean in the Insights screen?
It's the difference between your shortest and longest recent cycle length. A variation of ±4 days or less is shown as 'regular'; a larger spread indicates more variability in your pattern.
My cycle runs about 32 days — is that a problem?
Cyca is not a medical tool and cannot tell you whether your cycle length is clinically significant. A 32-day cycle is within the commonly cited adult range of 21–35 days. Any concerns about your cycle — length, regularity, symptoms — should be discussed with a qualified healthcare provider.