Hormonal healthDraft
Menstruation: the basics
What happens during your period, what can be 'normal' and when it is wise to see your GP.
5 min read · Published on October 28, 2026
This is draft content and will be editorially and professionally reviewed before publication.
Your period is when the lining of the uterus is shed. A cycle is counted from the first day of bleeding up to the day before your next period.
What can be normal?
- Cycles differ per person and per life stage. In adults a cycle often lasts somewhere between 21 and 35 days.
- A period usually lasts from a few days up to about a week.
- Small differences from month to month are common, for example due to stress, sleep, illness or travel.
When to see your GP
- Very heavy bleeding, for example needing to change a pad or tampon more often than every hour.
- Pain that clearly limits your daily life.
- Bleeding between periods or after menopause.
- Periods that suddenly change a lot or stop.
Tracking in Primal Ember
You can voluntarily track your period and symptoms. The app only shows your own patterns and a rough estimate of your next period. Primal Ember is not suitable as contraception and does not predict fertile days.