# Your First Period: What to Expect and How to Track It

> What a first period is usually like, why early cycles are often irregular, how to keep track and when to talk to a doctor. Written for teens and parents.

Page: https://period-tracker.org/guides/first-period/

Getting your first period is a normal part of growing up, and knowing what to expect makes it a lot less stressful. This guide is for teens and for parents who want to help.

Updated November 9, 2026

## What a first period is usually like

Periods usually start around age 12, but some people start earlier and some later. A period can last between 2 and 7 days, and about 5 days is common.

## Why early cycles are often irregular

For the first few years, periods often don't come on a regular schedule while your body settles into a pattern. Cycles longer than 38 days are common for a few years after a first period.

Keeping track helps you and your doctor see whether your cycles are getting more regular over time.

## How to keep track

The simplest way is to mark the first day of each period on a calendar. Add the day it ends if you can. After a few months you'll be able to see how far apart your periods are.

If you'd like to use Period Tracker, anyone 13 or older can [create a free account](https://period-tracker.org/). If you're under 18, look over the [Terms of Use](https://period-tracker.org/terms) with a parent or guardian and ask for their permission first. There's a first period option that keeps the dashboard simple, and accounts set to the Under 18 age group don't show fertility details in the calendar, emails or monthly reports.

## What to have with you

Your first period can start anywhere, including at school. It helps to carry a pad or two in your bag and to know how to use pads or tampons before you need them. A parent, school nurse or another trusted adult can help with this.

## When to talk to a doctor or a trusted adult

Talk to a doctor if:

-   Your periods haven't started by the time you're 15
-   A period lasts longer than 7 days
-   You miss 3 periods in a row
-   Anything about your period worries you

Asking questions about periods is normal. A parent, school nurse or doctor has heard them all before.

## Sources

-   [Periods](https://www.nhs.uk/conditions/periods/), NHS
-   [Irregular periods](https://www.nhs.uk/symptoms/irregular-periods/), NHS
-   [Missed or late periods](https://www.nhs.uk/symptoms/missed-or-late-periods/), NHS
-   [Your menstrual cycle](https://www.womenshealth.gov/menstrual-cycle/your-menstrual-cycle), Office on Women's Health
-   [Concerns Girls Have About Puberty](https://www.healthychildren.org/English/ages-stages/gradeschool/puberty/Pages/Concerns-Girls-Have-About-Puberty.aspx), HealthyChildren.org (American Academy of Pediatrics)

## Related tools

-   [Period Calculator](https://period-tracker.org/period-calculator/)
-   [Period Cycle Length Calculator](https://period-tracker.org/period-cycle-length-calculator/)