What is a menstrual cycle?
A cycle is the time from one period to the next.
- Period starts — Bleeding happens for a few days.
- Body builds a lining — The uterus gets ready again.
- Ovulation may happen — An ovary may release a tiny egg.
- Next period — If no pregnancy happens, a new period starts.
A cycle does not have to be perfectly regular to be normal, especially at first.
Quick answer
A menstrual cycle is the time from the first day of one period to the first day of the next period.
It is your body’s monthly pattern. Some people have regular cycles. Some people do not, especially when periods first start.
How long is a cycle?
A cycle is often talked about as around 28 days, but not everyone’s body follows that exact number.
For many people, cycles can be shorter or longer. In the first few years after periods start, it is common for them to be a bit irregular while the body settles.
What happens during the cycle?
- Your period starts. Blood and tissue leave the body through the vagina.
- The body builds a new lining. The uterus starts building a soft lining again.
- Ovulation may happen. An ovary may release a tiny egg.
- The next period may come. If the body does not need the lining, it leaves as the next period.
Why should I know about my cycle?
Knowing your cycle can help you understand when your period might come, whether periods are changing, if pain happens at certain times, and symptoms you may want to ask about.
How can I track my cycle?
You can write down the day bleeding starts, how many days bleeding lasts, whether bleeding is light, medium or heavy, cramps or pain, mood changes, and symptoms that worry you.
When should I ask for help?
Tell a trusted adult or healthcare professional if bleeding is very heavy, pain stops you doing normal things, you bleed between periods, feel faint or very unwell, or something feels wrong to you.
Ask Luma
You could ask: “What is a menstrual cycle?” or “How do I track my period?”
Final reassurance
Your menstrual cycle is your body’s pattern. It may take time to learn what is usual for you, and that is okay.