Why do periods happen?
Your body is growing and changing.
- Puberty starts — Your body begins to change.
- Hormones send messages — Hormones help the body know what to do.
- The uterus gets ready — It builds a soft lining each month.
- The lining leaves — If the body does not need it, it leaves as a period.
Periods are a normal part of growing up.
Quick answer
Periods happen because your body is growing and changing during puberty.
Each month, the body gets ready in case it might one day support a pregnancy later in life. If pregnancy does not happen, the lining inside the uterus leaves the body as a period.
What is puberty?
Puberty is the time when your body starts changing from a child’s body into a more grown-up body.
During puberty, you might notice:
- growing taller
- breast or chest changes
- hair under your arms or around your private parts
- body smell changing
- spots or oily skin
- mood changes
- discharge in your underwear
- periods starting
What is happening inside my body?
Inside the body, hormones send messages that tell different parts of the body what to do.
One of these messages tells the uterus to build a soft lining. If the body does not need that lining, it comes out through the vagina as period blood.
Does having a period mean I am ready to have a baby?
No.
Having periods means your body is developing. It does not mean you are emotionally, mentally or practically ready for pregnancy, sex or adult responsibilities.
You are still allowed to be a kid or teenager. Periods are just one body change.
Is everyone’s body the same?
No. Bodies develop at different speeds.
Some people start periods earlier. Some start later. Some have regular periods quickly. Others have periods that are irregular for a while.
When should I ask for help?
Tell a trusted adult or healthcare professional if you are worried about body changes, have very heavy bleeding, severe pain, feel faint or very unwell, or your periods stop you doing normal things.
Ask Luma
You could ask: “Why do periods happen?” or “Does having a period mean I am grown up?”
Final reassurance
Periods happen because your body is growing and changing. You deserve clear answers, support and time to understand your body.